A dozen Somali gunmen wearing government uniforms snatched two French security advisors from their hotel rooms in Mogadishu, officials and witnesses said Tuesday.

The French foreign ministry said in a statement the pair was "helping the federal transition government of Somali President Sharif Sheikh Ahmed in security matters."

It added that all the appropriate French agencies had been mobilised to find them, giving no further details about the two.

In Somalia, a senior government official who spoke to AFP on condition of anonymity said the two had been training the country's intelligence services.

"They were invited by the defence ministry to do some training for their counterparts in the Somali intelligence services. They have been in Somalia nine days," the official added.

No group claimed responsibility for the abduction, which took place in unusual circumstances since the gunmen encountered little resistance when they entered the Sahafi hotel where the two were staying.

"More than 10 gunmen on a military vehicle stormed the hotel early this morning. They disarmed the security guards and then went straight for the foreigners' rooms," Mohamed Ali, a police officer, told AFP.

"The incident appears to have been well planned because it occurred in a heavily-guarded area controlled by the Somali government," one member of the hotel staff said.

Several witnesses around the Sahafi, which also hosts several members of the Somali parliament, said some of the gunmen were wearing government uniforms.

They said no shots were fired as the kidnappers overpowered the security employees guarding the hotel entrance.

One witness told AFP that the kidnappers came with two vehicles.

"I saw a pick-up truck and another one with a dozen heavily-armed militants enter the hotel. I didn't realise something bad was happening until I saw two white guys in shorts being taken away at gunpoint," said Hasan Yare, a local grocer.

The Sahafi (journalist in Arabic) hotel is popular with foreign reporters and is close to the K4 junction where Ugandan peacekeepers from the African Union mission in Somalia (AMISOM) are stationed.

France and other Western military powers have pledged to support the development of the Somali security apparatus.

Sherif Sheikh Ahmed was elected as president of Somalia's transitional administration in January and received international backing but he has failed to assert his authority on the country.

Hardline Islamist insurgent groups launched a major military offensive to topple him two months ago, prompting Sharif and his government to make urgent appeals for foreign military assistance.

Somalia is one of the most dangerous countries in the world for local and foreign reporters alike.

Six Somali journalists have been killed since January alone and kidnappers have held two foreign freelance journalists -- Canada's Amanda Lindhout and Australia's Nigel Brennan -- since August last year.