An American drone has crashed in Somalia, a US official said Tuesday, after Shebab militants claimed to have recovered the wreckage.

"I can confirm an RPA (remotely piloted aircraft) crashed in a remote area of the Somali coastline south of Mogadishu," said the defense official, who spoke on condition of anonymity.

"The incident is under investigation," the official told AFP.

Officials declined to comment on what type of unmanned aircraft had crashed, whether it was armed and why it had gone down.

Somalia's Shebab insurgents said late Tuesday their fighters had recovered the wreckage of what they said was a crashed surveillance drone.

"This one is off the scrap yard," the Shebab said in a message on Twitter alongside photographs it said were "wreckage of a crashed US drone".

"This one will no longer be able to spy on Muslims again," the Shebab said. "So much for the empty rhetoric on the drone programme," they added, an apparent reference to a recent speech by US President Barack Obama on the use of the unmanned, robotic planes.

The Shebab said the drone crashed near the southern Somali village of Bulo Marer in the Lower Shabelle region, an area held by the extremists.

French commandos had raided the village in January in a failed bid to free a kidnapped colleague.

The sound -- or sight -- of surveillance drones are common in southern Somalia, and missile strikes also have reportedly been carried out.

The United States reportedly has drone bases in the region, including an airfield in Djibouti.

Shebab militants were driven out of the capital Mogadishu by African Union troops in August 2011, but the Islamists have carried out a series of brutal attacks in recent months.

Somali President Hassan Sheikh Mohamud's government, which came to power last year, remains weak and relies on the support of about 18,000 AU troops to stay in power.

In an address last week, Obama defended the use of drones but outlined new guidelines for US bombing raids against suspected extremists abroad.

The guidelines state that drone attacks can only be used to prevent imminent attacks and when the capture of a suspect is not feasible and if there is a "near certainty" that civilians will not be killed.