This is the terrifying moment mountain runoff surged down a waterfall and swept away tourists in the Philippines.

Raymond Guevarra and six of his friends had trekked to the Antag Falls in Davao City, Davao del Sur province, for a dip when the water suddenly gushed from higher ground on September 10.

The alarmed hikers hurriedly retreated, but several of them who were already swimming in the stream were caught in the raging currents. They managed to survive by clinging onto boulders before being pulled to safety by the rest of the group.

Raymond said: 'We didn't expect the water to surge so violently. I'm relieved we all made it out alive. It's a learning experience for us.'

The Philippines and neighbouring countries in Southeast Asia are in their annual monsoon rainy season which sees soaring temperatures followed by powerful rain storms in the afternoon leading to widespread flash floods.