U.S. launches strikes against Islamic State group in Nigeria after attacks target Christians

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,...