WASHINGTON (Reuters) - Two U.S. service members were killed during an operation against Islamic State militants in eastern Afghanistan overnight on Wednesday, U.S. officials said on Thursday, as President Donald Trump’s administration looks to craft a strategy in the war-torn country.

U.S. forces in Afghanistan said in a statement that a third U.S. service member was wounded in the raid, carried out with Afghan National Defense and Security Forces (ANDSF) against the militants.

A spokesman for the U.S. military in Afghanistan, Captain William Salvin said the deaths occurred in the same valley where the United States had dropped a massive bomb on a complex of fortified tunnel being used by the Islamic State.

Nicknamed “the mother of all bombs,” the GBU-43 Massive Ordnance Air Blast bomb was dropped from an American MC-130 aircraft in the Achin district of Nangarhar province, bordering Pakistan.

The incident comes just days after U.S. Defense Secretary Jim Mattis visited Afghanistan and U.S. troops are battling suspected Islamic State militants in Nangarhar province.

In this raid, Afghan commandos and coalition forces killed some 40 Islamic State fighters during a joint operation, said Attahullah Khogyani, a spokesman for the Nangarhar governor.

Khogyani said the raid was carried out against an Islamic State hideout in Achin district and some 13 militants were taken alive.

Another U.S. soldier was killed earlier in April while carrying out operations against Islamic State in the same province.

The Islamic State’s offshoot in Afghanistan, known as the Sunni jihadist group’s so-called Khorasan Province, is suspected of carrying out several attacks on minority Shi’ite Muslim targets.

U.S. officials say intelligence suggests Islamic State is based overwhelmingly in Nangarhar and neighboring Kunar province.

Estimates of its strength in Afghanistan vary. U.S. officials have said they believe the movement has only 700 fighters but Afghan officials estimate it has about 1,500.