MOGADISHU, Somalia - He was a teacher at an Islamic school, known in his hometown in northwestern Somalia as a talkative, religious man with a sense of humor.

He has also been identified as a suicide bomber who tried to bring down an airliner.

Abdullahi Abdisalam Borleh boarded a plane on Feb. 2 with a bomb that exploded at 11,000 feet. The blast created a hole in the fuselage of the Airbus 321, just above the wing, and Borleh was blown out, his body falling to earth and landing in the Somalian town of Balad.

Borleh said he was going abroad for health reasons, according to Sheikh Mohamed Abdullahi, a mosque imam in Hargeisa near where Borleh was from, and who met with him in January. Abdullahi estimated Borleh's age at between 50 and 52, described him as "chatty," and said that he had a leg problem that required him to sometimes walk with a cane.

On Saturday, al-Shabab, Somalia's Islamic extremist rebels, claimed responsibility for the attempt to destroy the plane with 81 passengers and crew aboard. The al-Qaeda-linked group mocked efforts to prevent such attacks and threatened more "to purify this Muslim land from the filth of the disbelievers."

There are mounting signs that al-Shabab had inside help.

A senior civil aviation security officer who supervised operations of screening machines at Mogadishu airport was one of 20 people arrested after he was seen on CCTV accompanying another man who handed the laptop believed to contain the bomb to Borleh after he had gone through security. The other man, identified as an airport employee, was also among those arrested.

The flight on Feb. 2 was supposed to have been on Turkish Airlines, but the airline canceled because of bad weather from a previous departure point, and Dubai-based Daallo Airlines was instead used. Flight 159 consequently took off an hour late, a delay which may have saved the passengers and crew.

If the bomb had gone off at cruising altitude, as it might have if it was rigged to a timing device set to coincide with the original flight time, the result could have been catastrophic, with the plane possibly disintegrating because of the vast difference between air pressure inside and outside at 30,000-plus feet.

Instead the blast happened earlier, at a lower altitude. Borleh was the only fatality and the plane's controls were unaffected by the blast, allowing the pilot able to fly the plane back to Mogadishu safely.