MANILA—A landslide struck Mount Apo following a 6.5-magnitude quake that rocked southern Mindanao Thursday, leaving hundreds of workers and residents trapped, a local official said.

Jorie Mae Balmediano, spokesperson of the Office of Civil Defense-Soccsksargen, said no one was injured, but the landslide blocked a road in Sitio Tayaban, Barangay Ilomavis in Kidapawan City, Cotabato.

The road leads to a geothermal plant owned by Energy Development Corporation (EDC). Clearing operations will begin Friday morning, Balmediano said.

The EDC, in a statement released Thursday, said all their employees were safe.

"Our M1 and M2 power plants in Mount Apo were initially affected and were put on turning gear operation only," it said.

"Structural assessments of our facilities will be conducted but right now, our priority is the safety of our employees, their families, and our community in Barangay Ilomavis."

The EDC said some 1,400 residents from their partner community in the area have been assisted.

"We are also coordinating with local government units, government agencies and our Barangay Emergency Response Team (BERT) to monitor the situation and will send our Disaster Preparedness and Rescue Unit from our Manila head office to provide the necessary assistance," it said.