Veteran of the Gulf War who trained for notoriety with the chilling motto: One shot, one kill

The man suspected of being the sniper who has killed 10 people in the Washington area, was trained by the best. Not only did John Allen Muhammad serve in the US military in the 1980s and 1990s, including a stint on active duty during the Gulf war; he was also, for many years, attached to a West Coast army base famous for its sniper training programme.

The programme's motto: "One shot, one kill." A Defence Department official who spoke to reporters yesterday said Mr Muhammad was an expert marksman who earned several badges and ribbons during his years in the army and was known to be particularly proficient with an M-16 assault rifle.

In the swirl of information that spilled out in the first hours after the arrest of Mr Muhammad, 41, and John Lee Malvo, the 17-year-old believed to be his stepson, it was not entirely clear what the suspect had learned during his years in the military, or what sorts of psychological and behavioural testing he had undergone before being given the skills to exercise lethal force on his fellow human beings.

But the wall-to-wall media coverage of his case and the troubling questions it raises are likely to cause considerable embarrassment to the military establishment, especially at a time when Americans are being asked to throw their support behind the flag for a possible invasion of Iraq.

After all, it wasn't so long ago that another Gulf War veteran, Timothy McVeigh, used his military skills to commit mass murder on a horrific scale with the Oklahoma City bombing. Could Mr Muhammad, like McVeigh, have been brutalised by his experiences of combat and transformed from a govern-ment-trained killing machine into an anti-government, anti-American radical?

The first signs certainly point that way. The young Mr Muhammad, born John Allen Williams, was described by his first wife yesterday as quiet, friendly and non-violent. By the time he split up with his second wife in 1999, however, it was a different story. Court records show that his spouse twice accused him of domestic violence and sought a court protection order against him. She also accused him of stealing their three children once their divorce proceedings were underway.

"I am afraid of John," Mildred Green Muhammad wrote in a complaint on 3 March 2000. "He was a demolition expert in the military. He's behaving very, very irrational. Whenever he does talk with me, he always says that he's going to destroy my life and I hang up the phone."

Other acquaintances described how he became a drifter after leaving the army in 1995. He converted to Islam after the break-up of his first marriage 17 years ago ­ hence the name change ­ and may have taken on more radical political views in the recent past. He became involved in Louis Farrakhan's black separatist movement, the Nation of Islam, and volunteered as a security guard at the Million Man March on Washington a few years ago.

The police officials who tracked him down said he spoke approvingly of the 11 September attacks on the Pentagon and the World Trade Centre and the radical anti-American ideology behind them. Officials do not believe, however, that he had links to al-Qa'ida or any other radical Islamic group.

Gleaning details of his army career was difficult yesterday, not least because the military chose to divulge absolutely nothing about him. In the 1980s he served at Fort Lewis, outside Tacoma, Washington, whose sniper assessment programme is used, amongst other things, to select candidates for the Army's élite Sniper School at Fort Benning, Georgia. The Fort Lewis course teaches snipers to work in pairs, with one man acting as the trigger and the other as a look-out ­ the pattern apparently followed in the Washington-area shootings.

It is not yet known whether Mr Muhammad participated in the sniper programme, and if so whether he tried and failed to get into Fort Benning. (McVeigh's anti-government resentment began with his failure to qualify for the Special Forces.) Few details were forthcoming on his role in the Gulf war, or on a brief postwar stint he served at the now defunct base at Fort Ord in California.

One friend said yesterday he had served in the Green Berets, a branch of the Special Forces which has a group stationed at Fort Lewis. Military officials said, however, that he was not in the Special Forces. They said he had undergone basic firearms training and had expertise in combat support missions. Another Pentagon official said he had served as a combat engineer. They said nothing about the demolition expertise mentioned by his former wife.

From 1994 until earlier this year, he is believed to have lived in Tacoma, with periods of drifting around the country in between. Among other things, he helped to run a karate and martial arts school, where his partner Felix Strozier described him as a "pretty nice person" ­ at least until they fell out over an unpaid debt of Mr Muhammad's and closed down the school in 1998.

The Pentagon said he also spent eight years in the Army National Guard, attached to stations in Louisiana, where his brother and first former wife live, and Oregon.

It was one of his Tacoma homes that was raided by police on Wednesday after reports from the neighbours that he had fired weapons there nearly every day in January.

"It sounded like a high-powered rifle such as an M-16," said his neighbour Christ Waters, a army private stationed at Fort Lewis. "Never more than three shots at a time. Pow. Pow. Pow." The police removed a tree stump from the property after finding it was peppered with bullet holes.

Mr Muhammad and Mr Malvo were also traced to Bellingham, about 120 miles north of Tacoma, where Mr Malvo was briefly enrolled at the local high school. Both were reported to have moved to the East Coast earlier this year. Their last known address was in Clinton, Maryland, where some of their relatives also live.