From the moment the young man who called himself John Lee Malvo showed up at Bellingham High School in Washington more than a month into the school year in 2001, school officials had questions about him.

He didn't have transcripts.

He said he lived in a homeless shelter.

Two months passed, and the promised paperwork never arrived. So officials notified local police.

Malvo didn't exist on paper in his new American home. He and his mother had been smuggled from St. Elizabeth, Jamaica, to Haiti and then onto a tugboat into Miami, where they illegally entered the United States, according to accounts they gave to immigration officials.

Malvo, who is being held as a material witness in the sniper attacks that terrorized the Washington area for more than three weeks, made his way across the country with his mother, Una James, to Bellingham, Wash., where they lived in homeless shelters but began to take on some trappings of a routine life. Malvo entered high school and joined the local YMCA under a family plan, interviews show.

It was also in Bellingham, a college town in the northwest corner of the state, that Malvo and his mother spent time with John Allen Muhammad, the 41-year-old Persian Gulf War veteran now being held on a federal firearms violation and being questioned about the Washington area killings. After launching a nationwide manhunt, law enforcement officers arrested Malvo and Muhammad early yesterday as they slept in a car at a rest stop near Frederick.

Details of their lives are still emerging. At various points, interviews reveal, Muhammad and Malvo passed themselves off as father and son in Washington, Louisiana and New Jersey. Other times, Muhammad denied knowing the young man. Even official reports from immigration authorities and the Jamaican government differ on basic facts, such as the spelling of their names and ages for Malvo and his mother.

But it is clear that the lives of Malvo and Muhammad entwined long before officers surrounded their vehicle at the rest stop.

On Dec. 19, 2001, Bellingham police summoned immigration officials after police were called to a domestic disturbance between James and Muhammad, a U.S. Border Patrol report shows.

According to the report, an agent and a Bellingham officer following up on the domestic dispute tracked James to the Agape Women's Shelter. A local police officer said Malvo frequented the library and YMCA. An immigration officer found Malvo with Muhammad at the Y, where they had been playing basketball, according to interviews.

Malvo, who said he was 16 at the time, and James, then 37, were arrested on immigration charges by a Border Patrol agent and handed off to INS officials in Seattle. They were eventually released pending deportation hearings Nov. 20, nearly a year later.

Fingerprints that the INS took from Malvo ultimately helped thesniper task force identify him as someone they wanted to question, law enforcement sources said.

At the time of their INS arrest, Malvo and James were living in separate homeless shelters in Bellingham, they told the Border Patrol.

Muhammad, a U.S. citizen, was living at the same Bellingham shelter -- the Lighthouse Mission -- as Malvo at the time of the INS arrest, federal law enforcement sources said. When officers asked Malvo if he knew Muhammad, Malvo said yes, but Muhammad denied knowing the boy, law enforcement officials said.

Malvo and James were detained for about a month by the INS, James in Seattle and Malvo at a juvenile center in Spokane, law enforcement agents said.

James was later released on $1,500 bond, and Malvo was released on his own recognizance.

Some immigration officials yesterday contended that the pair should have been held as stowaways and held without bail. But officials at INS headquarters said that they did not meet the definition of stowaways and that their cases were appropriate.

"They should hold on to all of them," said Rich Pierce, executive vice president for the national Border Patrol Council, the union representing agents. "These were two illegals. They were both illegally here, and they let them both go."

An INS official in Washington said that the Border Patrol in Seattle had initially listed the pair as stowaways but that the charge was corrected by the INS to arriving illegally in the country. "It was not the correct charge," said the official.

Two months later, the Bellingham border agents got a call from the police officer who patrols the local high school: Malvo was back in class.

The police thought Malvo, who police sources here said was known in Tacoma as "Sniper," had been arrested and detained.

It was just one in a series of questions school officials had raised since Malvo and his mother first arrived. The presence of Muhammad only complicated matters.

Muhammad and Malvo told people that they met in Washington state and that they were father and stepson. In October 2001, the pair had joined the Y in Bellingham, a picturesque town near the Canadian border, signing up for a month-to-month family membership. The two used the weight room and played basketball in the gym, said Dave Harding, manager of the Bellingham YMCA.

"It was a pretty nondescript relationship," Harding said. "They didn't do anything different than any other father and teenage son who were working out."

Muhammad and Malvo stayed at the Lighthouse Mission, on the edge of the city and a 15-minute walk from the gym. Mission officials said Muhammad showed up on Oct. 20, 2001, and stayed through Jan. 19, 2002. They said that Muhammad was accompanied by a "teenage male whom John claimed was his stepson. This person was using the name Lee Malvo."

A resident at the shelter, who declined to give his name, said the pair stood out because of the differences in their ages.

"They were friendly and polite," he said.

The pair did not sleep in the 50-person bunk room because Malvo was a minor. Instead, residents said, they slept on cots set up in a mission hallway.

Though Muhammad was a Muslim convert, the pair spent an hour each evening at the mission chapel, one of the rules of the shelter. Residents said they did not appear to own a car and traveled about town on foot or by bus.

The month that Muhammad checked into the shelter, Malvo showed up at Bellingham High School. It was October 2001, but administrators admitted Malvo as a junior after he promised to have his transcripts and other records forwarded from a high school in the Southeast.

"There were questions about Mr. Malvo's attendance at the school," Bellingham Police Chief Randy Carroll said yesterday. "He was there without transcripts or documents."

On Dec. 18, 2001, Bellingham police interviewed Malvo as part of a "suspicious persons case" raised by school officials. Carroll described Malvo as a "pretty quiet kid" who spent a lot of time in the library and "didn't really establish a circle of friends."

Carroll said police became concerned because Malvo said he and his father lived in a homeless shelter. "It was a humanistic level of suspicion," the police chief said. He said officers also were concerned that Malvo could have been a runaway or a minor living with a man who was not really a relative.

Malvo told police that he had moved to Bellingham from Jamaica and that Muhammad was his father. But the teenager was vague when asked where he lived previously in the United States and where he attended high school prior to arriving in Bellingham, Carroll said. Soon after the interview, Carroll said, Malvo withdrew from the school and "basically disappeared."

Carroll said FBI agents have obtained Malvo's records from Bellingham High School and plan to examine his handwriting to determine whether it matches with words written on a tarot card or the notes left at the scenes of sniper shootings in Maryland and Virginia.

Last night, Jamaican authorities said their records show a Lee Boyd Malvo as having been born in Kingston, Jamaica, on Feb. 18, 1985, to Una James of St. Elizabeth and Leslie Samuel Malvo of St. Andrew.

Jamaican records also note that a Lee Malvo attended high school in Jamaica prior to emigrating in 1998 to another Caribbean island at age 13.

Local school records show no evidence of disruptive behavior and listed a "satisfactory" academic record, the officials said.

Malvo's father was shaken by the news. Leslie Malvo, 55, told the Associated Press in Kingston that he last saw his son four years ago. "This morning I woke up and heard the news, and I said, 'That sounds like my son,' " said Malvo, a building contractor in Kingston. "He was a nice kid, so I don't know how he got mixed up in this."