BOGOTA, Colombia –  Colombia’s police chief says leftist rebels have killed seven police officers and injured five in an ambush in the country’s northwest.

National Police Gen. Rodolfo Palomino tells The Associated Press that members of the Revolutionary Armed Forces of Colombia bombed a truck that was carrying 14 police officers on a road in Tierradentro in Cordoba province, 415 kilometers (258 miles) northwest of the capital, Bogota.

Palomino said that seven officers were killed, five were seriously injured and two were uninjured in Tuesday’s attack.

That attack comes amid ongoing peace talks between the leftist rebel group and the government of President Juan Manuel Santos being held in Havana, Cuba. Santos has warned that continued attacks by the rebels could undermine the peace process.