• The al-Shabab militant group said it had carried out the attack, using a car bomb to blast through the gates before sending its fighters inside.
• Military officials say the jihadists have been pushed back.
Jihadists have attacked a military base where US soldiers train commandos in Somalia, causing casualties, reports say.
Local residents on Monday reported heavy blasts and gunfire at Baledogle airport in the southern Lower Shabelle region.
The al Shabab militant group said it had carried out the attack, using a car bomb to blast through the gates before sending its fighters inside.
Military officials said the jihadists have been pushed back.
Al Shabaab said in a statement it had launched the raid and that it was ongoing.
"After breaching the perimeters of the heavily fortified base, the mujahideen [holy warriors] stormed the military complex, engaging the crusaders in an intense firefight."
The base, about 100km west of the capital Mogadishu, is said to house US special forces, Somali special forces and Ugandan peacekeepers. It is used as a launch site for US drones as well as being a training centre.
Separately, an Italian military convoy was hit by an explosion in Mogadishu itself, Italy's defence ministry said. No casualties have as yet been reported in this attack.
The US has sharply increased its air strikes against al Shabaab, which is linked to al-Qaeda, since President Donald Trump took power.
Officials in Somalia say the group has increased its attacks in Mogadishu as retaliation for the air strikes.