A wave of explosions rocked southwest Colombia on Tuesday morning, authorities said, killing at least seven people in an attack believed to be targeting the country’s police.

Southwest Colombia has been rocked by a series of explosions and gun attacks near police stations that have left at least four people dead, according to police, an apparent coordinated attack that authorities have blamed on rebel groups.

Coordinated attacks against police stations have occurred in the last few days in the province of Valle del Cauca and the city of Cali, including car bombs, explosive charges, and shooting attacks