At least 17 people were killed when a bus plunged down a 100ft-deep ravine in the Philippines.

The vehicle carrying dozens of passengers was headed for Cusi town in Antique province when it allegedly lost its brakes while turning an 'accident-prone' curve on December 5 afternoon.

The bus crashed through guardrails and fell off a cliff in Hamtic town at around 4 pm.

Footage shows rescuers searching the wreckage for injured passengers, with several bodies lying next to the destroyed coach. Survivors on makeshift stretchers were carried up the ravine by the responders.

The rescue operation continued late into the evening due to the steepness of the ravine and lack of mobile signal in the area.

Officials said that as of December 6 morning, 17 people, including the bus driver, had died in the accident. Seven people were in critical condition, while four others were safe, the provincial disaster office said.

Roderick Train, head of the Antique disaster agency, said: 'This is a mountain road, so the bus fell from a high place. That's why the impact caused many casualties. This Hamtic-Iloilo road is an accident-prone area and what happened, based on the witnesses, was a mechanical failure. The driver lost control, possible brake failure.'

In a statement, Antique governor Rhodora Cadiao added: 'For the families, it's not right for me to say ‘don't worry'. But we'd like to assure you that whatever hospitalization, medicines, and what they need we will take care of that.'

Meanwhile, bus operator Vallacar Transit, Inc. (VTI) said the company was ready to cooperate in investigations, adding 12 other buses under the franchise until the matter has been resolved.

The company's statement read: 'VTI will be providing assistance to the passengers and their families, as well as shouldering the medical and burial expenses.'

Road safety is a problem in the Philippines, where poor infrastructure, lax enforcement of traffic regulations, and a high number of road users, result in frequent accidents.