LIMA (AFP) - At least 12 police officers were killed Tuesday (Dec 12) in Peru when the bus transporting them plunged off a cliff, falling some 700 metres, the national police chief said.

Another 13 officers were "gravely injured" in the crash in the Andes mountain region of Apurimac, police director general Vicente Romero told the N news channel.

TV images showed the totalled bus lying on the banks of a river at the bottom of a steep valley.

Rescue workers and firefighters were recovering bodies and attending to the injured.

The bus was carrying 32 officers in all when it ran off the road around dawn near the southern district of Antabamba, Romero said.

"We are coordinating to mobilize helicopters to the area to transport the injured," he said.

The officers were on their way to provide security for a meeting between government officials and Antabamba residents who have been protesting for better public services.

Deadly road accidents are common in Peru. They killed 2,798 people in 2014, the last year for which official statistics are available.