President Donald Trump said Thursday that US forces conducted deadly strikes against Islamic State "Scum" in northwestern Nigeria, and vowed more attacks if the militants keep killing Christians.

Without providing details, the commander in chief said "The Department of War executed numerous perfect strikes," on Christmas Day, against IS targets.

"I have previously warned these Terrorists that if they did not stop the slaughtering of Christians, there would be hell to pay, and tonight, there was," Trump posted on his Truth Social platform.

"May God Bless our Military," he said, adding provocatively, "MERRY CHRISTMAS to all, including the dead Terrorists, of which there will be many more if their slaughter of Christians continues."

US Africa Command said in an X post that it conducted a strike "at the request of Nigerian authorities...killing multiple ISIS terrorists."

Pentagon chief Pete Hegseth took to X to praise his department's readiness to take action in Nigeria, and said he was "grateful for Nigerian government support & cooperation."

The attacks mark the first by US forces in Nigeria under Trump, and come after the Republican unexpectedly berated the west African nation in October and November, saying Christians there faced an "existential threat" that amounted to "genocide" amid Nigeria's myriad armed conflicts.

The diplomatic offensive was welcomed by some but interpreted by others as inflaming religious tensions in Africa's most populous country, which has seen bouts of sectarian violence in the past.

Nigeria's government and independent analysts reject framing the country's violence in terms of religious persecution -- a narrative long used by the Christian right in the United States and Europe.