U.S. forces carried out airstrikes in Somalia on Saturday targeting a senior Islamic State group attack planner and other members of the militant group, killing many of them, President Donald Trump said.

"These killers, who we found hiding in caves, threatened the United States and our Allies," Trump said in a post on Truth Social.

"The strikes destroyed the caves they live in, and killed many terrorists without, in any way, harming civilians."

Saturday's strikes were carried out in the Golis Mountains and an initial assessment indicated many militants were killed, Secretary of Defense Pete Hegseth said. No civilians were harmed, he said.

Reuters could not independently verify those details.

The Somali president's office said President Hassan Sheikh Mohamud was informed of the airstrike, and he wrote on X that he extended his deepest gratitude for "the unwavering support of the United States in our shared fight against terrorism."

"Your bold and decisive leadership, Mr. President, in counterterrorism efforts is highly valued and welcomed in Somalia."

The information minister for Puntland state in northern Somalia said the U.S. attack struck in the Cal Miskaad Mountains, part of the Golis range, and targeted Islamic State group bases.

"The number of casualties is still unknown as it was dark. But our forces on the frontline could hear the sound of explosions,” the minister, Mohamud Aidid Dirir, told Reuters.

Hegseth said the strikes degraded the Islamic State group's ability to plot and carry out attacks that threaten the United States, its partners and innocent civilians.

"(It) sends a clear signal that the United States always stands ready to find and eliminate terrorists who threaten the United States and our allies, even as we conduct robust border-protection and many other operations under President Trump’s leadership," he said in a statement.

The United States has periodically carried out airstrikes in Somalia for years, under Republican and Democrat administrations.