Sen. John McCain, chairman of the Senate Armed Services Committee, said on Thursday that he may consider issuing a subpoena because the White House has not been forthcoming with details of an ambush in Niger in which four U.S. soldiers were killed.
The attack earlier this month, which U.S. officials suspect was carried out by a local Islamic State affiliate, has thrown a spotlight on the U.S. counterterrorism mission in the West African country, which has about 800 U.S. troops.
The U.S. military is investigating the incident to find out what went wrong and what, if any, changes need to be made.