Accused in the Ketan Agarwal murder case Siya Goyal being taken to court from Vadgaon Maval Police Station, in Lonavala on July 3, 2026.
| Photo Credit: ANI

The story so far: A Pune court has extended the custody of Siya Goyal and Chetan Chaudhary, the two accused in the Ketan Agarwal murder case, until July 3, 2026. The court acquiesced to the investigators, who said several aspects of the probe are ongoing, including a forensic study of Mr. Chaudhary’s gait. According to media reports, the police plan to compare the way he walks with CCTV footage showing a hooded individual near the crime scene at Lohagad Fort, arguing that the analysis could help determine whether the person in the footage was Mr. Chaudhary.

What is gait analysis?

Gait analysis is the scientific study of how a human walks or runs. Walking (or running) is a complex activity where the body has to coordinate continuously between muscles, bones, and the nervous system. Gait analysis breaks down these activities to piece together how a particular person walks.

In clinical settings, this analysis can be used to understand why someone is in pain or how a specific medical condition is progressing. Sportspersons use it to understand how they can run faster.

Likewise, forensic gait analysis has been used to assess whether the way a person walks — as recorded live or seen on CCTV footage — is consistent with that of a known individual. It is generally used as the sole piece of evidence and is usually considered to corroborate other findings, such as DNA data and/or eyewitness accounts.

In most instances, experts use the analysis to identify abnormalities in an individual’s pattern of movement. For example, sometimes a person’s back pain may be related to the way their foot strikes the ground. Doctors also use gait analysis to manage symptoms in people with cerebral palsy and Parkinson’s disease and as part of post-stroke care.

In fact, in Parkinson’s disease, Alzheimer’s disease, dementia with Lewy bodies, and multiple sclerosis at least, research has found that changes in gait can appear years before their more obvious symptoms.

What is a gait cycle?

To understand the way a person moves, experts begin with looking at the gait cycle — the series of events starting from the moment one foot touches the ground until the same foot returns to the ground again.

The cycle has two broad phases. In the stance phase, your foot is in contact with the ground and ends when the toes push off. The body absorbs the shock of hitting the surface while supporting your whole body weight in this phase. In the swing phase, the foot is off the ground but also moving towards it, to take the next step. In this duration, the body’s focus is on ensuring the toes don’t drag on the floor while positioning the foot for its landing.

During gait analysis, an individual makes multiple gait cycles while experts use instruments to track the steps per minute, step length, stride length, the angles of the legs’ joints, ankle rolls, and the force with which the foot strikes the ground. Sometimes, the instruments are just a clinician’s eyeballs and a notepad, so as you walk back and forth, they record different aspects of your movement.

These days, experts also record a person’s gait cycles on video and analyse it with a computer later, use sensors called pressure mats and force plates to track where your feet apply the most pressure, and wearable sensors attached to the person’s body to track their movement in a real-world setting, like at a crime scene or on a sports field.

How is forensic gait analysis different?

In forensic gait analysis, experts may be able to use a person’s walk to identify them in a video the same way a person’s fingerprint can be used to identify if they have touched a surface.

In the case of Ketan Agarwal’s death, the police have said they have a video of an individual near the scene of the crime and that it could be one of the suspects, Chetan Chaudhary. The person’s face in the video is obscured by a hoodie, however, so the police hope to confirm if that is indeed Mr. Chaudhary using gait analysis, among other methods.

In such cases, typically, experts such as podiatrists or human movement specialists compare two sets of videos: the footage being investigated and footage showing the suspect walking at a different place/time. They pay close attention to the rhythm of the steps, the angle of the feet, the way the arms swing, idiosyncratic movements like a slight limp or a peculiar tilt of the head, and so on.

The experts may conclude — for example — the person in both videos is the same if they both have a specific outward rotation of the right knee and an unusually short stride.

What are police doing in the Ketan Agarwal case?

Indian Express quoted an unnamed senior police officer as saying investigating officials will have Mr. Chaudhary dress “in his original hoodie attire” and then “walk again at the same spot at Lohagad Fort”. Then, the officer added, “the new video-recorded walk will be compared with that of CCTV footage recorded on June 18”.

According to the officer, the police will use “AI tools” to “analyse the similarity” and “help confirm his presence”.

Going by published research, here, the investigators might isolate the suspect’s gait from the CCTV footage on June 18 and — depending on the video quality — assess the relative movements of the hips, knees, ankles, shoulders, etc. and/or evaluate the silhouette.

Then, when the suspect is made to walk near the crime scene in the same attire, the gait will be recorded again and evaluated. By doing this at the scene of interest itself, the experts may be able to reproduce the effects of factors such as the camera angle, perspective, slope, and lighting.

Finally, experts may compare the gait between the original footage and the new footage to score the similarities — a task for which the unnamed police officer said artificial intelligence (AI) tools will be used.

What are the challenges in gait analysis?

Researchers have already pointed to some pitfalls in this technique. One example is quality issues in the CCTV footage. Another is that most published gait-recognition systems calculate a similarity score or ranking. However, a high score only means the movements resemble each other according to some model; it does not establish that the same person appears in both videos.

The act of asking someone to recreate a walk may also change the walk. People generally can’t reproduce an earlier gait exactly. And if they know they are being compared to CCTV footage, they may consciously or unconsciously alter their speed, stride length, posture, arm swing, etc.

Researchers have also called for larger studies that quantify error rates in CCTV footage recorded in realistic conditions, including when AI models are used as part of criminal investigations. These models could produce misleading scores if the use case differs from the typical ones in the models’ training data.

There is also ongoing debate about how unique a person’s gait could really be and the ability of different instruments to identify that uniqueness. For example, cameras recording at different frequencies, say 30 Hz versus 250 Hz, the latter will be better able to capture some motion that happens within 20 milliseconds as the other will have a frame delay of 33.3 milliseconds.

Depending on the gap between the crime and the investigation, experts may also have to account for differences in gait due to age, sex, height and leg length, and body mass changes.

These are just some of the reasons gait analysis by itself is not used as dispositive evidence to identify a person. Forensic researchers generally recommend gait analysis or comparison be interpreted together with independent evidence such as location data, witness testimony, DNA, fingerprints, and/or other forensic findings.

“CCTV footage showing a hooded man, later identified as Chetan Chaudhary, trailing Ketan Agarwal and his fiancée Siya Goyal at Lohagad Fort near Pune alerted police probing the businessman’s death,” police said on Wednesday (June 24, 2026).

Police found it unusual that the man was wearing a hoodie despite the temperature being around 33 degrees Celsius, and his overall suspicious movements prompted them to probe Ketan’s death further, which initially appeared to be a tragic trekking accident.

In a deadly twist to what would have been a dream wedding, police on Tuesday (June 23, 2026) said 26-year-old Ketan, who died while on a trek on June 18, was allegedly pushed into the gorge by his fiancée Siya (20) and her lover Chetan (22).

Watch: Pune fort murder: Police allege Fiancée, lover pushed man into gorge

Ketan Agarwal, who was engaged to Siya earlier this year, died after falling from a cliff at the historic fort on June 18. The incident was initially registered as an accidental death, with Siya informing the victim’s family that he had slipped during the trek.

“While investigating the case, we stumbled upon certain circumstances surrounding the incident that raised suspicion and prompted a deeper probe. We checked CCTV cameras installed at the ticket counter of the fort, where we spotted Ketan and Siya walking together,” said a police officer who was part of the probe.

While examining the footage minutely, police noticed a man who was a few metres behind Ketan and Siya.

“The man was wearing shorts and a hoodie. The front part of the hoodie was pulled so low that his face could not be seen. Additionally, the man was wearing a headset over the hoodie. In another footage clip, we noticed Siya suddenly looking back and, at the same time, the man in the hoodie suddenly sitting down,” the official said.

He said they later checked the temperature of that particular time on June 18 and found out that it was 33 degrees Celsius and wondered why would anyone wear a hoodie in such heat.

The officer said police could not immediately inquire about the couple as Ketan’s family was grieving, but during the probe, it was learnt from Ketan’s uncle that Siya had earlier expressed reservations about the marriage and had once asked whether the wedding could be postponed by a year.

Siya and Ketan got engaged in February and were scheduled to get married in a grand wedding ceremony at Udaipur in November, for which a palace had been booked.

“During inquiries with Ketan’s sister, Sanjana, and other family members, we came to know that Siya had repeatedly persuaded Agarwal to accompany her to Lohagad Fort on multiple occasions before the fatal incident. On May 31, Siya had taken Ketan to Lohagad Fort. She again insisted that he go to Lohagad Fort on June 4. However, Ketan’s mother did not allow him to go there a second time,” the officer said.

He said Siya and Chetan wanted to “eliminate” Ketan before she and the businessman were scheduled to leave for Bali for a pre-wedding photoshoot. That trip did not materialise as Ketan’s passport mysteriously went missing before the trip.

“Siya once again insisted that Ketan go to Lohagad on June 14. On that day, she allegedly tried to push Ketan off the cliff. However, he managed to hold on to a bush. When Ketan wondered why he had been pushed, she raised a false alarm about a snake and tried to make it appear that she had protected him,” the officer said.

He added that following these developments, investigators widened the probe and analysed technical evidence, including call detail records and digital communication data.

According to him, scrutiny of Siya’s call records showed extensive communication between her and a contact who turned out to be her lover, Chetan Chaudhary.

“We found thousands of calls exchanged between the two over an extended period, including several conversations lasting for hours.

“The technical analysis established a close connection between the duo and pointed towards a well-thought-out conspiracy. We then examined photographs and social media profiles linked to Chaudhary. A comparison of those images with CCTV footage from the fort showing a hooded individual in the area helped police narrow their focus on him,” he said.

He added that based on the technical evidence and intelligence gathered by the Lonavala Rural Police Station and the Local Crime Branch (LCB), teams traced and detained Chaudhary for questioning. “During interrogation, we connected all the dots, which revealed a premeditated conspiracy involving Siya and Chetan,” he said.

Police said the motive appeared to stem from Siya’s relationship with Chetan and her unwillingness to proceed with the marriage to Ketan.

“During the interrogation, Chetan was asked why they did not consider running away and instead chose to eliminate Ketan. According to him, Siya was not in favour of calling off the engagement and eloping with Chetan, as she thought doing so would bring disrespect to her family,” he said.

Police subsequently arrested both Siya and Chaudhary and booked them on charges of murder and criminal conspiracy.

Ketan, a resident of Gahunje in Pune district, was a director and chief marketing officer Success Group, the family-run real estate business. He had done MS in Entrepreneurship, while Siya held a degree in commerce from a private college.

Published – June 24, 2026 11:51 am IST