Two attacks against mayoral candidates in Mexico’s June elections have left nine persons dead in the southern state of Chiapas, the Prosecutor’s Office in the organised crime-plagued region said on Sunday.

The two candidates survived, though one was wounded, in the onslaughts on Saturday night and early Sunday in the municipalities of Villa Corzo and Mapastepec, it said in a statement.

The attacks marked an escalation of violence in Chiapas against politicians intending to seek office in the June 2 vote, when Mexicans will also elect a new President.

Last week, six persons, including a minor and mayoral candidate Lucero Lopez, were killed in an ambush.

More than two dozen politicians have been killed since September last year, according to the NGO Data Civica.

The toll increases to more than 50 people if relatives and other victims of those attacks are counted.

Spiraling criminal violence has seen more than 4,50,000 people murdered in Mexico since the government of then-president Felipe Calderon launched a controversial military offensive against drug cartels in 2006.