A US Navy SEAL has been killed and two troops wounded in a clash with al Shabaab militants in Somalia, US officials say, in what appeared to be the first US combat death in the country since the 1993 "Black Hawk Down" disaster.
The White House has granted the US military broader authority to carry out strikes in Somalia against al Qaeda-linked al Shabaab, the latest sign President Donald Trump is increasing US military engagement in the region.
US Africa Command said a service member was killed by small arms fire on Thursday while US forces were advising and assisting a Somali National Army operation in Bariire about 60 km west of Mogadishu. They did not give further details on the identities of any of the three casualties.
A US official, speaking on condition of anonymity, said the man who was killed was a US Navy SEAL. It was not immediately clear whether the wounded US forces were also from the elite US military organisation.
"Although US forces are not engaged in direct action (in Somalia), advise and assist missions are inherently dangerous," said Robyn Mack, a spokeswoman at the US military's Africa Command.
"US forces are assisting partner forces to counter al-Shabaab in Somalia to degrade the al-Qaeda affiliate's ability to recruit, train and plot external terror attacks throughout the region and in America," it said in a statement.
In Friday's incident, US troops were hunting an al Shabaab commander near the Shabelle river alongside Somali special forces, a Mogadishu-based security source told Reuters. There were no Somali casualties.
A spokesman for al Shabaab, which wants to overthrow the weak Western-backed Somali government and impose its own strict brand of Islamic law, said US troops had attacked one of their bases.
Somalia has been shattered by civil war that began when clan-based warlords overthrew a dictator in 1991 and then turned on each other.
A US military intervention there in 1993 ended after the "Black Hawk Down" incident, when 18 US soldiers were killed after Somali militia shot down two US helicopters in the capital Mogadishu.
African Union peacekeeping forces have been in Somalia since 2007, gradually expanding from the airport to secure the capital and eventually pushing into other major towns.