Rescue personnel transfer an injured person of a bus accident in Pasamayo, north of Lima, capital of Peru, on Jan. 2, 2018. At least 25 people were killed near Peru's capital on Tuesday when their bus plummeted 400 meters off a highway and into a gorge, the Highway Police (POLCAR) said. (Xinhua/ANDINA/Vidal Tarqui)

LIMA, Jan. 2 (Xinhua) -- At least 25 people were killed near Peru's capital on Tuesday when their bus plummeted 400 meters off a highway and into a gorge, the Highway Police (POLCAR) said.

The bus was carrying some 50 passengers when it collided into an oncoming trailer truck around midday and skidded off the road about 48 kilometers north of Lima, in a location known as Pasamayo.

Officials said the trailer truck had entered the wrong lane and was to blame for the accident.

National news service Andina published an image of the crash site, showing the wreckage of the bus landed upside down on the rocky banks of the river below.

An undetermined number of injured passengers were taken to area hospitals.

More than 20 firefighting units, backed by a helicopter, were on hand to retrieve the bodies and extract survivors, though the location of the bus at the bottom of the gorge made rescue work difficult.

The tragedy occurred at a dangerous turn in the road known as the "Devil's Curve."

Passengers were headed to Lima and had boarded the bus in Huacho, some 150 kilometers north of the capital.