Scores of residents fled a Somali rebel stronghold close to the capital on Monday after what appeared to be a night-time missile strike targeting a militant base.

People in the town of Afgoye, about 30 km (20 miles) outside the capital Mogadishu, heard a loud explosion late on Sunday from the direction of a known al Shabaab base, housed in former government buildings.

Some residents said there had been a flurry of insurgent activity in the area on Sunday amid rumours that some of the rebels' top commanders were meeting.

I am sure there was a meeting going on in the base near the orphanage. Armoured cars and expensive 4x4s were buzzing around yesterday afternoon, Afgoye resident Osman Odowa told Reuters.

One of the missiles struck right around there, Odowa said.

Afgoye is a strategic junction on the road leading from the capital to the south of the Horn of Africa nation. A senior al Shabaab official said two missiles were launched from warships off the anarchic country's shores.

Enemy warships in the Indian Ocean fired two missiles at us last night, the official, who declined to be named, told Reuters by telephone.

There were no casualties, he said. It was not possible to verify his account.

One missile landed on a football field near an orphanage, the rebel official said. The other missile struck a waste ground near an area dubbed Kilometre 50, located 50 km from the capital, he added.

Residents living between the coastal capital, epicentre of al Shabaab's almost five-year insurgency, and Afgoye said they saw a bright light streaking overhead in the night sky on Sunday.

It was not clear who fired the missiles. The United States has used drones in the past to target top al Shabaab officials. In 2008, a drone attack killed Aden Hashi Ayro, said at the time to be al Qaeda's boss in the Horn of Africa.

Kenya sent hundreds of troops across its border into Somalia five weeks ago to crush the Islamist militants and has warned of air strikes on rebel enclaves across central and southern Somalia.

A fleet of foreign battleships are also patrolling the strategic sea-lanes off Somalia where pirates prey on commercial vessels and private yachts for ransom.

I have already evacuated and am now passing the town of Elasha, mother-of-five Samira Farah told Reuters, referring to the al Shabaab-controlled town 17 km outside of the capital. Mogadishu is our destination.

A column of minibuses laden with mattresses was following, she said. Who dares to stay in a place which is a target of planes and warships? she said.

After a fairly smooth advance, Kenya's forces fighting al Shabaab have been camped near several rebel strongholds, but have yet to have a major showdown with the insurgents, nor seize any significant strategic bases.