WASHINGTON (AP) -- Al-Qaida is confirming the death of its No. 3 official, Mustafa al-Yazid, as well as members of his family.

A U.S. official says al-Yazid was believed to have died in a U.S. missile strike.

A statement posted on an al-Qaida website describes al-Yazid as the organization's top commander in Afghanistan. It says he was killed along with his wife, three daughters, a grandchild and other men, women and children but did not say how or where.

The statement was dated by an Islamic calendar month which falls in May.

A U.S. official in Washington says word of the death was "spreading in extremist circles" in the past two weeks.

The official says the death would be a major blow to al-Qaida, which in December "lost both its internal and external operations chiefs."

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