Matthew Scott is recovering at a Colombian army medical base

Londoner Matthew Scott, 19, was found by Indians in the Sierra Nevada mountains after wandering for 12 days.

He fled while on a forced march, he told reporters from his hospital bed. He had survived only on water.

There was no word on the other seven hostages - another Briton, four Israelis, a Spaniard and a German - who were snatched with him on 12 September.

Mr Scott's parents, speaking from their London home, said they were praying for the other hostages but were "thrilled" their son was free.

We were walking on the mountain and the sides were very steep, I heard the river and I jumped off a cliff very quickly Matthew Scott In pictures: Matthew Scott's story

The backpacker was worried he had been a nuisance but was looking forward to eating a baked potato, said his father James, 60.

The kidnapped tourists were snatched after hiking to Colombia's "Lost City," a spectacular 2,500-year-old ruin nestling in the mountains.

The eight had been part of a larger group of 15 tourists who were sleeping in a cabin when armed guerrillas, described by witnesses as aged 18 to 20, burst in.

'Very happy'

After careful selection the other seven were not taken, either because they were physically unfit or did not have sturdy walking shoes, they told reporters.

Mr Scott told journalists that he escaped shortly afterwards, when it was raining and there was poor visibility.

"We were walking on the mountain and the sides were very steep," he said.

"I heard the river on the right hand and I followed the sound. I jumped off a cliff very quickly. I was lucky to not have broken my arms and legs."

Mr Scott was suffering exhaustion, dehydration and sunburn when he was found, and had cuts from jungle plants, but is expected to make a full recovery.

"I only drank water," he said.

"I did not eat anything during the last 12 days. When I found these people they gave me a soup made with beans and a little salt and three oranges."

If you go outside certain areas there is a good chance you will run into trouble Kidnap victim Paul Winder Kidnap danger to tourists

The locals said he was "dizzy and vomiting" when they found him.

"He was very happy. He said he thought he was going to die, he said he was happy," an unnamed local woman said.

Local reports said a massive manhunt was on for the remaining hostages.

The military commander leading the hunt said he would be able to "readjust" the search based on Mr Scott's information.

BBC correspondent Jeremy McDermott, in Bogota, said the fact they had not spotted Mr Scott in the 12 days he had been wandering suggested they were looking in the wrong place.

'Sheer hell'

Colombian President Alvaro Uribe has blamed the Cuban-inspired National Liberation Army for the kidnapping.

The rebels use ransom money to finance a four-decade-old guerrilla war.

Mr Scott himself said he had no idea who the kidnappers were.

"Every person of that group said different things. Some of them say they are paramilitaries, they all say different things," he said.

More than 1,000 people have been kidnapped in Colombia since the beginning of the year.

Sierra Nevada is a disputed territory, fought over by Marxist guerrillas, right-wing paramilitaries and drugs traffickers.

The other Briton is 31-year-old TV producer Mark Henderson from Lincoln, who now lives in London.

Alistair Taylor, an oil worker from Aberdeen who spent almost two years as a hostage of left-wing guerrillas, said the hostages would be going through "sheer hell" as their captors tried to evade pursuers.

He earlier told BBC News Online: "They will be marched, they won't get a minute's rest.

"The guerrillas are going to be as scared as them. They need to get them hidden, the army is looking for them. They will be under a lot of pressure, keeping them moving."