The corpses of 31 people were discovered in recent days in secret tombs in the southeastern state of Chiapas of Mexicowhich is facing an escalation in violence linked to organized crime, local authorities said.

“Until today (yesterday, Monday), we have found a total of 25 secret graves and 31 bodies, 29 men and two women,” Jorge Luis Yaven, the prosecutor of Chiapas state, said in a statement.

Last Saturday, the government of that state announced the discovery of 15 bodies in the Frailesca district, a rural area not far from Guatemala that has been plagued by criminal gangs for three years.

Another two bodies were discovered on Sunday and then 14 yesterday, Monday, he clarified.

He added that his office and the state security secretariat are continuing the search until “all the bodies of people who have disappeared” are found.

Authorities also announced the arrest of a man who may be involved in “enforced disappearances.”

According to local media, rival gangs are clashing over control of drug trafficking routes through kidnappings and extortion.

Along with almost two decades of violence linked to drug trafficking, the discoveries of secret graves, some of which contained more than a hundred bodies, in various regions of the country have multiplied in Mexico.

On Thursday, the prosecutor’s office in the state of Chihuahua (northern Mexico), on the border with the US, had reported the discovery of 12 bodies in other secret graves.

Since authorities launched a controversial campaign against drugs in December 2006, more than 450,000 people have been murdered and tens of thousands have disappeared in Mexico, according to official figures.