US forces carried out a fresh air strike in southern Somalia on Monday, a senior US official has said.
An AC-130 gunship reportedly staged the strike
The official, speaking on condition of anonymity, gave no details about the operation, at least the second US strike in Somalia this month.
A Pentagon spokesman said the US would continue to pursue members of al-Qaeda, wherever they were.
The US has long said al-Qaeda militants linked to the 1998 US embassy bombings in East Africa took refuge in Somalia.
The Washington Post newspaper quoted unnamed US officials as saying that a US Air Force AC-130 gunship carried out the Monday strike.
It said the operation was carried out in close co-operation with Ethiopian forces, which last month helped Somalia's interim government to drive south Islamist fighters from the capital, Mogadishu.
The Pentagon has confirmed that US aircraft targeted al-Qaeda suspects in the first air strike on 8 January but has not said whether it was successful.
There have been reports that as many as 20 people were killed in that strike.
In a separate development, Nigeria became the latest African nation to agree send up to 1,000 troops as part of an African Union (AU) peacekeeping mission to Somalia.
The AU has proposed sending some 8,000 peacekeepers to bolster the interim government after Ethiopian troops complete their withdrawal from Somalia.
So far only Uganda and Malawi have formally pledged to send troops.