BOGOTA, Colombia — A 7.4-magnitude earthquake struck western Colombia Monday, killing at least 20 people and prompting evacuations across the region.

The epicenter was near San José del Palmar in Colombia's Chocó region, approximately 400 kilometers west of the capital, Bogota. The U.S. Geological Survey reported the quake occurred at a depth of about 107 kilometers. Colombia's geological service initially estimated the magnitude at 6.6.

The mayor of Pereira said 18 people died in the city. Two more died in Manizales.

Chocó Gov. Nubia Carolina Córdoba-Curí said injuries and significant building damage occurred in Quibdó, the regional capital, and expressed concern about aftershocks. Authorities are conducting a damage assessment.

In Bogota, the quake set off car and building alarms, sending residents into the streets. Mayor Carlos Galán said there were no injuries in the capital, only some building cracks, and that Bogota's resources were available to assist affected areas.

Footage broadcast by news outlets showed destroyed buildings in Pereira and Manizales, both in Colombia's Eje Cafetero tourist region. Authorities in Colombia and neighboring Ecuador urged residents to remain alert as emergency teams assess the full extent of the damage.

The earthquake follows two powerful tremors that struck Venezuela in late June. Those quakes, measuring 7.2 and 7.5 in magnitude, killed more than 6,000 people and destroyed hundreds of buildings, making them among the deadliest in the region in recent years.