The team looking for a missing backpacker in Malaysia has said the search has been narrowed to a smaller area.
Gareth Huntley from Cricklewood, north London, has not been seen since going trekking on Tioman Island last Tuesday.
Johari Jahaya, the man leading the rescue team, said clues meant they could reduce the area being searched.
Prime Minister David Cameron has spoken to his Malaysian counterpart about the search.
Mr Jahaya would not elaborate on what the clues were which led to the search are being cut down but he said 39 people are now looking for Mr Huntley.
Mr Huntley's mother Janet Southwell said she believed her son had been injured but was still alive.
She arrived in Malaysia on Monday and said she wanted to join the search for her son.
She told the BBC: "I want to see the area for myself, absolutely, get a feel for where he's lost, where he's missing.
"I just want to be here when they find him, I think he will want to see a familiar face when they find him."
The British Government said it had been assured "all available search assets" were involved in the hunt, which includes police officers and rescue teams.
A spokesman for Number 10 said David Cameron had spoken to Malaysian prime minister Najib Razak and thanked him for the efforts made by authorities over the past few days to find Mr Huntley.
Mr Huntley, 34, set off to visit a waterfall on the island, off the south-eastern coast of the country's mainland, on Tuesday.
He told friends he would be back at the charity project where he was volunteering by 14:00, but failed to return.
Last week, his family raised concerns about the rescue effort.
His brother Mark said police did not initially join the search and for days it was only his friends and local people who were looking for him.
The British Defence Secretary Philip Hammond, who was in Malaysia, "was assured that the Malaysian authorities would do all they could to locate him and had already deployed significant assets", the Foreign Office said in a statement.
On his official Twitter feed, the Malaysian Defence Minister Hishamuddin Hussein also said he was helping to find missing Mr Huntley.