WASHINGTON — Federal authorities on Saturday charged a 23-year-old Nigerian man with trying to blow up a Detroit-bound airliner on Christmas Day, and officials said the suspect told them he had obtained explosive chemicals and a syringe that were sewn into his underwear from a bomb expert in Yemen associated with Al Qaeda.

The authorities have not independently corroborated the Yemen connection claimed by the man, Umar Farouk Abdulmutallab, who was burned in his failed attempt to bring down the airliner and is in a hospital in Michigan. But a law enforcement official briefed on the investigation said on Saturday that the suspect’s account was “plausible,” and that he saw “no reason to discount it.”

Mr. Abdulmutallab’s name was not unknown to American authorities. His father, a prominent Nigerian banker, recently told officials at the United States Embassy in Nigeria that he was concerned about his son’s increasingly extremist religious views.

As a result of his father’s warning, federal authorities in Washington opened an investigative file and Mr. Abdulmutallab’s name ended up in the American intelligence community’s central repository of information on known or suspected international terrorists.

Members of Congress who were briefed Saturday by governmental officials also pointed to a Yemeni connection.

“The facts are still emerging, but there are strong suggestions of a Yemen-Al Qaeda connection and an intent to blow up the plane over U.S. airspace,” Representative Jane Harman, a California Democrat who leads the House Homeland Security subcommittee on intelligence, said in a statement.

The attempt prompted significant changes to airline security around the world during the busy holiday season.

In an affidavit filed in support of the criminal charges, the authorities said that Mr. Abdulmutallab had tried to ignite a device, which was attached to his body, resulting “in a fire and what appears to have been an explosion.”

The affidavit said the device contained PETN, also known as pentaerythritol, a highly explosive substance that was used in 2001 by Richard C. Reid, the so-called shoe bomber whose attempt to blow up a trans-Atlantic flight was also thwarted. Officials said analysis of the remnants of Mr. Abdulmutallab’s device was being carried out by the F.B.I. laboratory, but it was possible that had the chemical mixture detonated, it might have brought down the aircraft.

The suspect’s name was inserted last month into the Terrorist Identities Datamart Environment, or Tide. About 550,000 individuals are registered in the database. A subset of that is the Terrorist Screening Data Base, or T.S.D.B., which has about 400,000.

By contrast, fewer than 4,000 names from the T.S.D.B. are on the “no-fly” list, and an additional 14,000 on a “selectee” list that calls for mandatory secondary screening, an Obama administration official said. At the time Mr. Abdulmutallab’s name was recorded in the Tide database in November, the official said, “there was insufficient derogatory information available” to warrant putting him in the T.S.D.B., no-fly or selectee lists, and so he was not on any watch list when he boarded the plane bound for Detroit.

President Obama ordered a full review of the law enforcement and intelligence databases related to the no-fly list to make sure the procedures and practices still make sense, a senior administration official said Saturday.

Mr. Abdulmutallab was issued a regular visitor’s visa by the United States Embassy in London in June 2008, the administration official said. There was no “derogatory information available” on him at the time he applied, and he was granted a two-year visa, which is still valid, the official said. He had traveled to the United States once before, to Houston in August 2008.

Representative Bennie G. Thompson, a Mississippi Democrat who leads the House Homeland Security Committee, said in a telephone interview that he would hold hearings next month when Congress returns from its recess to determine whether airport screening processes were at fault, scanning equipment was inadequate, information was not shared among federal agencies, or human error was to blame.

Mr. Abdulmutallab told F.B.I. agents he was connected to the Qaeda affiliate, which operates largely in Yemen and Saudi Arabia, by a radical Yemeni cleric whom he contacted online. The cleric is not believed to be Anwar al-Awlaki, an American-born imam who has spoken in favor of anti-American violence and who corresponded with Maj. Nidal Hasan, the Army psychiatrist charged in the killings of 13 people in a shooting spree last month at Fort Hood, Tex.

In a statement, the Yemeni Embassy in Washington said: “We have yet to receive official information on the incident. If and when the would-be bomber’s alleged link to Yemen is officially identified, authorities will take immediate action.”

If corroborated, Mr. Abdulmutallab’s travel to Yemen for terrorist instruction and explosives underscores the emergence of that country as a major hub for Al Qaeda, perhaps beginning to rival the terror network’s base in Pakistan.

For years, American counterterrorism officials have watched Yemen with trepidation as an unstable state with multiple security challenges and an uncertain commitment to battling extremists who see their main enemies in the West.

But this month has seen an unprecedented assault by the Yemeni government on Qaeda strongholds, with major airstrikes on Dec. 17 and Dec. 24, which may have killed as many as 60 militants.

The Yemeni government initially said it believed the second strike had killed the top two officials of Al Qaeda in Yemen as well as Mr. Awlaki, the American-born cleric, whose popular Web site and radical sermons have turned up as an influence in a dozen recent terror cases in the West.

But American officials said they had no confirmation of the cleric’s death, and Mr. Awlaki’s relatives told The Associated Press on Saturday that he was still alive.

Mr. Abdulmutallab grew up in a rarefied slice of Nigeria, the son of an affluent banker. He attended one of the West Africa’s best schools, the British School of Lomé in Togo. After high school, he went to Britain and enrolled at University College London to study mechanical engineering.

While still in high school, Mr. Abdulmutallab began preaching to fellow students about Islam, according to a report in ThisDay, a Nigerian newspaper. The newspaper reported that more recently, Mr. Abdulmutallab had moved to Dubai in the United Arab Emirates and told his family that he no longer wanted to associate with them.

His father, Alhaji Umaru Mutallab, until recently served as chairman of the First Bank of Nigeria, and his mother’s family is originally from Yemen, according to news accounts in Nigerian newspapers.

Charles Anaman, 26, who now lives in Ghana, said that he was close friends with Mr. Abdulmutallab in high school — they would listen to music, watch videos, play basketball.

Mr. Abdulmutallab was like most other students at the school, Mr. Anaman said, with a particular interest in studying history, and a preference for hip-hop music.

Mr. Anaman said that his involvement in the Detroit incident was hard to imagine: “He was a very calm person.”