The bodies of one man and two women, reportedly aged 19 and 25, have been recovered downstream of the Datanla Waterfalls (pictured above) in the central Lam Dong province - a popular tourist spot.

Police are questioning one man on suspicion of taking the group on an unauthorised tour.

Their cause of death has not been confirmed, but the group are thought to have slipped and fallen while exploring the area, Vietnam's Thanh Nien News quoted one local police chief as saying.

Vo Anh Tan, deputy director of the Lam Dong joint stock tourist company that manages the Datanla Waterfalls, said the group did not pay for entrance tickets and did not use the company's safety gear.

The Foreign Office has said it is providing support to the families of the Britons.

"Our sympathies are with the families and friends at this difficult time," it said in a statement. "We are in close contact with local authorities in Vietnam on their behalf."

The identities of the three have not been confirmed, but state-run media said the two women entered the country at the start of the month.