Two U.S. airstrikes killed several Islamic State militants in northeastern Somalia on Friday, the military announced.

The strikes occurred midnight and 11 a.m. local time, and a statement from U.S. Africa Command said officials are assessing the results. The statement said the strikes were conducted in coordination with the government.

"U.S. forces will continue to use all authorized and appropriate measures to protect Americans and to disable terrorist threats," AFRICOM said, adding that targets include terrorists, training camps and "havens throughout Somalia."

The announcement comes as President Trump promised to hit ISIS "10 times harder" after a man drove a truck into pedestrians in New York City. On Thursday, ISIS leadership referred to the attacker as "a Soldier of the Caliphate."

"They claimed him as a soldier, good luck. Every time they hit us, we know it's ISIS, we hit them like you folks won't believe," Trump told reporters Friday morning at the White House.

The strikes also come amid heightened concern over the spread of ISIS in Africa, after militants claiming an affiliation with ISIS ambushed U.S. soldiers in Niger on Oct. 4, killing four.