Updated

NOUKACHOTT, Mauritania -- A suspected al-Qaida militant killed himself by detonating an explosive belt to avoid capture Saturday as security forces arrested his alleged accomplice in connection with an explosion earlier in the week, an army official said.

The army had cornered the two in Lexeiba, about 150 miles (250 kilometers) south of Nouakchott, after a three-day search, according to the military officer, who could not be named because he was not authorized to speak to the media.

The two men allegedly had been part of a convoy of cars loaded with explosives that had entered Mauritania last week. Security forces opened fire Wednesday on one of the cars, which was loaded with explosives, as it attempted to speed into the capital, setting off an enormous explosion and killing three suspected al-Qaida-linked militants.

The militants may have been targeting the French Embassy. The assailants abandoned the second car in the desert, and soldiers were searching for a third which is believed to be carrying supplies.

The North Africa franchise of al-Qaida claimed responsibility for the attempted attack on a website in Mauritania, saying their target was the president of Mauritania who campaigned on an anti-terror platform and whose government has collaborated last year with the French military during a cross-border raid on a militant camp in Mali.

Defense Minister Hamadi Ould Hamadi, however, said the interrogation they carried out with one of the suspected militants arrested earlier in the week indicated the target was the French Embassy.

Once a sleepy desert nation, Mauritania has been fighting recently against the North African cell of al-Qaida, which grew out of an insurgency in neighboring Algeria. The group has financed its growth by kidnapping dozens of foreigners, whose governments are believed to have paid ransoms for their release. Their attacks are becoming more brazen and in January, the cell grabbed two French nationals from a restaurant in the capital of Niger.