Bilal al-Sudani, the regional leader of IS in Somalia, was a "key facilitator" for the group's global network, said US Secretary of Defense Lloyd Austin.
"This action leaves the United States and its partners safer and more secure, and it reflects our steadfast commitment to protecting Americans from the threat of terrorism at home and abroad," Austin said in a statement.
What do we know about the operation?
US President Joe Biden ordered the operation, which was carried out on Wednesday, Austin said.
According to US officials, al-Sudani and 10 other IS fighters were killed in a gunfight after US forces descended on a mountainous cave complex to capture him.
Who was Bilal al-Sudani?
Media reports, citing US officials, said al-Sudani was involved in recruiting and training fighters for the al-Qaida-linked group al-Shabab before he joined IS.
He reportedly coordinated funding for IS operations in Africa and the group's branch in Afghanistan, the Islamic-State Khorasan (IS-K).
"Al-Sudani was responsible for fostering the growing presence of [IS] in Africa and for funding the group's operations worldwide, including in Afghanistan," Austin said.