SAN'A, Yemen - Yemeni forces raided an al Qaeda hideout and set off a gunbattle yesterday as the government vowed to eliminate the group claiming to be behind the Christmas bombing attempt on a U.S. airliner.

The fighting took place in an al Qaeda stronghold in western Yemen, haven for a group that attacked the U.S. Embassy here in 2008, killing 10 Yemeni guards and four civilians. A government statement said that at least one suspected militant was arrested during the clashes.

Al Qaeda in the Arabian Peninsula, an offshoot of Osama bin Laden's group, claimed that it was behind the attempt to bomb a Detroit-bound airliner. Nigerian Umar Farouk Abdulmutallab, 23, was arrested Friday after he allegedly tried to bring down the Northwest Airlines flight, carrying 289 people.

U.S. investigators said that Abdulmutallab told them that he received training and instructions from al Qaeda operatives in Yemen. Yemen's government has said that Abdulmutallab spent two periods in the country, from 2004-2005 and from August to December of this year, just before the attempted attack.

Abdulmutallab's Yemen connection has drawn attention to al Qaeda's growing presence in the impoverished and lawless country, which is located on the tip of the Arabian Peninsula across the Gulf of Aden from Somalia.

The U.S. has increasingly provided intelligence, surveillance and training to Yemeni forces during the past year, and has provided some firepower, according to a senior U.S. defense official, who requested anonymity.

Defense Department spokesman Bryan Whitman said that Yemen received $67 million in training and support under the Pentagon's counterterrorism program last year, second only to some $112 million spent in Pakistan.

In Holland, the Dutch government issued a preliminary report yesterday calling the airliner plot professional, but describing the execution as "amateurish."

Dutch Interior Minister Guusje Ter Horst told a news conference that Abdulmutallab apparently assembled the explosive device, including 80 grams of PETN, in the aircraft toilet, then planned to detonate it with a syringe of chemicals. She said that the explosives appeared to have been professionally prepared and then given to Abdulmutallab.

Meanwhile, officials told the Associated Press yesterday that a man tried to board a commercial airliner in the Somali capital of Mogadishu last month carrying powdered chemicals, liquid and a syringe in a case bearing chilling similarities to the Detroit airliner plot.

The Somali - whose name has not yet been released - was arrested by African Union peacekeeping troops before the Nov. 13 Daallo Airlines flight took off. It had been scheduled to travel from Mogadishu to the northern Somali city of Hargeisa, then to Djibouti and Dubai.

The aborted attack in Detroit was launched almost a year after al Qaeda's operations in Yemen and Saudi Arabia united to form al Qaeda in the Arabian Peninsula, making Yemen its base.

Shortly after al Qaeda in the Arabian Peninsula was formed, Saudi Arabia announced a list of 85 most wanted militants outside its borders.

It said that 11 of them were former Guantanamo detainees who had gone through its rehabilitation program. Three were confirmed to have gone to Yemen. They included Abu al-Hareth Muhammad al-Oufi, who later surrendered in Yemen and was handed over to Saudis; Said al-Shihri, the group's No. 2; and Youssef al-Shihri, who was killed in a clash with Saudis in southern Saudi Arabia.

The Yemeni roots of the attack threaten to complicate U.S. efforts to empty the U.S. prison at Guantanamo Bay, where nearly half the remaining detainees are from Yemen.

Finding a home for them is key to President Obama's pledge to close the prison, but emerging details of the plot are renewing concerns about Yemen's capacity to contain militants and growing al Qaeda safe havens.

Rep. Mike Castle, R-Del., noted that of the 90 men remaining at Guantanamo, more than 60 have been identified as dangerous by the Pentagon.

"Yet, in the past few weeks, the Obama administration has overseen the repatriation of six Yemenis from Guantanamo back to their home country," he said. "As we learn more about Abdulmutallab's ties to Yemen and AQAP, it is increasingly clear that the transfer of detainees from Guantanamo is a flawed process demanding immediate review."

Abdulmutallab spent about five months in Yemen leading up to the airliner attack and a year before that in 2004-2005, Yemeni officials said.

Administrators at the San'a Institute for the Arabic Language said that he was enrolled at the school during both periods to study Arabic. But staff and students said that he spent at most one month at the school starting in late August. His time through December is unaccounted for.

Acquaintances described the strict Islamic life that he led, rejecting music, TV and mixing with women. All of them expressed surprise that the quiet man they knew would even consider to carry out such an act.

"I saw him once tenderly kiss a baby," said Ahmed Mohammed, a teacher at the institute.

"Today, he's turned into a monster who would have killed children if the operation had succeeded."

Also yesterday it was reported that Abdulmutallab spent two weeks in Houston last year at a seminar conducted by a Web-based Islamic education center.

Waleed Basyouni is the vice president of the AlMaghrib Institute. He says that Abdulmutallab registered online in April 2008, then attended a two-week program hosted by the institute in Houston in August 2008.

He says that school records show that Abdulmutallab identified himself as a 21-year-old Nigerian student at University College London and the London School of Economics who was studying mechanical engineering and business finance.

Basyouni says that the institute is working with the authorities on the case.