Twenty-nine years on, a Pentagon task force finds the remains of Howard Dean's brother

Howard Dean, the leading Democratic presidential candidate, has revealed that the remains of his younger brother have been found in Laos, 29 years after he disappeared on a trip down the River Mekong.

Mr Dean said members of the Pentagon's task force that search for missing servicemen, prisoners of war and civilians, had discovered the remains in a crude grave in a paddy field in central Laos. While tests have yet to be completed Mr Dean said he was 99.9 per cent sure the remains were his brother, Charlie.

"This has been a long and very difficult journey for my mother, and for my brothers and for myself", Mr Dean said. "We greet this news with mixed emotions but we're gratified and grateful that we're now approaching closure on this very difficult time in our lives". The announcement of the discovery in Bolikhamxai province has turned attention to the work of the POW/MIA Task Force that spends $103m every year searching for the remains of prisoners of war and troops missing in action from the Second World War and Korea, Vietnam and Gulf Wars.

It will also likely give Mr Dean's campaign a boost, by humanising a candidate often criticised for being cold and distant. Mr Dean said he and his brothers shared the news with their mother on Monday night at a fund-raising party in Washington for his 55th birthday.

Mr Dean's brother, younger than him by 16 months, disappeared in 1974 at the height of the Vietnam war. Charlie, aged 23, was travelling through south-east Asia with an Australian friend, Neil Sharman. After spending a month of so in the Laotian capital, Vientiane, the two left on a ferry, intending to travel to neighbouring Thailand. Mr Dean said they had been told in 1975 that Charles had been killed after being taken hostage by communist Pathet Lao rebels on September 4, 1974.

Mr Dean's parents went to Laos to search for Charles but found nothing. Mr Dean, who had grief counselling in the 1980s to deal with his brother's death, travelled to Laos himself last year to look into the disappearance. "When you go through something like this you have a tremendous sense of survivor guilt and anger at the person who disappears and then guilt over the anger - it's very complicated" he said. In an autobiography Mr Dean said his parents believed his brother had been a spy though he had never seen any evidence to support this. A CIA spokeswoman said yesterday: "We never comment on an individual's employment. We neither confirm or deny."

Larry Greer, a Pentagon spokesman, said 1,785 troops and civilians were still listed as missing in south-east Asia - 78,000 from World War II, 8,100 from the Korean War, 126 from the Cold War and three from the Gulf War. The task force recently found the remains of a US airman in Britain.

"There is an unwritten military motto that you don't leave anyone behind," he said. "Sadly some soldiers had to leave their comrades behind." Mr Dean is due to go to Hawaii for the repatriation of his brother's remains where further tests will be carried out.