New Delhi, Dec. 27 -- President Donald Trump said the United States launched a "powerful and deadly" strike against forces of the Islamic State group in Nigeria, after spending weeks accusing the West African country's government of failing to rein in the targeting of Christians.

In a Christmas evening post on his social media site Thursday, Trump did not provide details or mention the extent of the damage caused by the strikes in the northwestern state of Sokoto.

A Defense Department official, who insisted on anonymity to discuss details not made public, said the U.S. worked with Nigeria to carry out the strikes and that they'd been approved by Abuja.

Nigeria's Ministry of Foreign Affairs said the cooperation included exchange of inte...