WASHINGTON (AP) — President Barack Obama says he authorized the attempt to rescue American Luke Somers in Yemen because the U.S. had information that the American photojournalist's life was in imminent danger.

That word from the White House came shortly before a security official in Yemen said al-Qaida militants had planned to kill Somers on Saturday.

Authorities said Somers and a South African aid worker died in the U.S. rescue attempt.

Obama says U.S. forces conducted the rescue operation in partnership with Yemen's government.

The president also says the U.S. "will spare no effort" in trying to rescue any American held hostage anywhere in the world.

Secretary of State John Kerry says the murders are "a reminder of the brutality of the terrorists of Al-Qa'ida in the Arabian Peninsula (AQAP)." Kerry says the extremists have again proven their cruelty and their disdain for human life, freedom, and the Yemeni people whom they terrorize daily.

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