At least four people were killed in Colombia as rebel groups detonated bombs near police stations in the city of Cali and the neighboring Cauca province, according to Colombian authorities.

A series of explosions were reported in the Colombian city of Cali on Tuesday morning. The city’s mayor, Alejandro Eder, said authorities were “responding to two explosive devices in our city: one at the Meléndez police station and another at the Manuela Beltrán CAI.”