"Farouk1986" introduced himself to a Muslim online community with these words in February 2005.

"My name is Umar but you can call me Farouk," the poster continues, detailing biographical information that appears to match the life of Umar Farouk AbdulMutallab, the 23-year-old Nigerian man accused of attempting to detonate an explosive on an international flight into Detroit, Michigan, on Christmas Day.

The failed terror plot put airports on high alert and refocused American attention on al Qaeda in the Arabian Peninsula, which claimed responsibility for the attempted attack.

Internet postings for Farouk1986 -- apparently a combination of his name and birth year -- reveal a young man who fought feelings of loneliness and struggled with balancing his life as a Muslim with the temptations of the secular world around him. He wrote about his desire to attend university, possibly in the United States, and his thoughts on love and marriage.

Officials have not confirmed that Internet postings by Farouk1986 were made by AbdulMutallab, but the many detailed biographical points made by the poster match what has been reported about AbdulMutallab's life.

"I will describe myself as very ambitious and determined, especially in the deen," Farouk1986 wrote in February 2005, referring to the Islamic way of life. The poster writes about being in boarding school, with possibilities of attending Stanford University or the University of California-Berkeley.

Eventually, AbdulMutallab studied mechanical engineering at University College London.

Besides being ambitious, Farouk1986 also described himself as lonely.

"First of all, I have no friend[s]," he wrote in another online post with informal, imperfect grammar. "Not because I do not socialise (sic), etc but because either people do not want to get too close to me as they go partying and stuff while I don't. or they are bad people who befriend me and influence me to do bad things.

"i have no one to speak too, no one to consult, no one to support me and i feel depressed and lonely. i do not know what to do."

Somewhere along the way, AbdulMutallab turned toward Islamic extremism.

An FBI official said AbdulMutallab was included in the U.S. government's Terrorist Identities Datamart Environment, or TIDE, after his father warned the U.S. Embassy in Nigeria of his son's hard-line beliefs and possible ties to militant Islamists. But his name was not pulled from that database and included on lists barring him from U.S.-bound aircraft.

Part of the explosive device that failed to take down last week's flight from Amsterdam, Netherlands, was sewn into AbdulMutallab's underwear, authorities said. A preliminary FBI analysis found the device contained pentaerythritol tetranitrate, an explosive also known as PETN.

Investigators were having trouble determining what the accelerant AbdulMutallab allegedly tried to use to light the explosives because "the syringe was pretty much destroyed," a law enforcement source told CNN.

All 300 passengers and crew onboard the Christmas Day flight have been interviewed by authorities, the source said, adding that he expected no one else to be held or charged in connection with the incident.

Farouk1986's online posts show that as early as 2005, he had a serious view of his religion. One of his struggles, the poster wrote, was that the "loneliness leads me to other problems."

Farouk1986 said after fasting, "I felt a shield that prevented evil thoughts coming into my head. I felt closer to Allah."

Being lonely awakened sexual desires that he struggled to control, he said, sometimes "leading to minor sinful activities like not lowering the gaze." His religion instructed him to fast to avoid such temptation, but it didn't seem to be working, Farouk1986 said.