Mexico City, Jan. 2: At least 14 people died in a brazen armed assault on a prison in the Mexican border city of Juarez on Sunday, officials said.

The Chihuahua state attorney general’s office said in a statement, that 10 security guards and four prisoners were killed and 13 others were injured.

The incident began around 7 a.m. (9 a.m. ET) on Sunday when gunmen in armoured vehicles arrived at the prison and opened fire on security personnel, the prosecutor’s office said.

Authorities said inmates took advantage of the situation and 24 prisoners escaped.

It was not immediately clear who was behind the attack.

CNN has reached out to the attorney general’s office for more details about the status of the investigation.

Ciudad Juarez, just across the US-Mexico border from El Paso, Texas, is one of Mexico’s deadliest cities and an epicentre of drug cartel violence. The rival Juarez and Sinaloa cartels have been fighting a bloody turf war in the region over lucrative smuggling routes and drug-dealing territory in the city.

Sunday’s violence was not the first time violence has erupted at the prison. Last August, hundreds of Mexican troops were sent there after a clash between the two cartels caused a riot and shootouts that killed 11 people.-Agencies