The strike a day earlier was near a "terrorist encampment location" in the Hiran region of central Somalia, US Africa Command said in a statement.

The action came as part of an ongoing mission in which US forces work with African Union and Somali national security forces to fight the Shabaab jihadist movement.

Such "strikes continue to help our partners make progress in their fight against the transnational terrorists who oppose peace in Somalia and in the region," said Major General Gregg Olson, Africa Command director of operations.

The Pentagon has increased the rate of strikes in Somalia in recent years, partly because President Donald Trump loosened constraints on when the US military can take action against alleged terrorists.

Although the military did not specify in its latest statement, such air strikes in Somalia are typically carried out by armed drones.

Earlier in January Africa Command said a strike killed 52 Somali militants, and last month the US military said it had killed 62 Shabaab militants during six air strikes in the Horn of Africa nation.

In October, the military said it conducted its largest air strike in nearly two years against militants in Somalia, killing about 60 Shabaab fighters, who are battling to overthrow the internationally supported government in Mogadishu.

Shabaab fighters were pushed out of Somalia's capital in 2011, and subsequently from other towns and cities, by African Union troops.

But the Islamists still hold sway in large parts of the countryside.

They launch regular gun and bomb attacks on government, military and civilian targets in Mogadishu as well as ambushes on military convoys and outposts.