Officials in Colombia say at least seven police officers have been killed in an attack.

Authorities say the officers’ car hit a landmine and then gunmen launched an attack on the vehicle.

The New York Times reports that the youngest police officer killed in the attack in southern Colombia was 18 years old.

President Gustavo Petro, a former guerrilla, posted on Twitter that the attack was “a clear act of sabotage against peace.”

There has been no immediate claim of responsibility for the attack.

Colombia signed a peace deal with the rebel group the Revolutionary Armed Forces of Colombia, or FARC, in 2016, but that pact has not prevented a recent wave of violence.