* Same restaurant was hit a year ago
* Security threats persist despite al Shabaab exit from Mogadishu (Adds background, context)
By Abdirahman Hussein and Abdi Sheikh
MOGADISHU, Sept 7 (Reuters) - A car bomb and suspected suicide bomber struck a restaurant in the Somali capital Mogadishu on Saturday, killing at least 15 people, police said.
It was not immediately clear who carried out the attack on the popular Village Restaurant, owned by Somali businessman Ahmed Jama, who had returned to his home country from London to set up business against the advice of friends.
But suspicion will likely fall on the Islamist militant group al Shabaab, which has carried out a campaign of suicide bombings despite withdrawing from the city in 2011 under military pressure.
Ahmed Nur, a senior police officer at the scene, told Reuters that at least 15 people had been killed.
Mohamed Yusuf, spokesman for the Mogadishu authorities, said that after the car bomb went off, a suicide bomber immediately blew himself up in the restaurant.
"First a car bomb exploded at the entrance of the restaurant, and when people converged inside a suicide bomber blew up himself," he said.
A Reuters witness at the scene described a tangle of mangled tables, chairs, blood and pieces of human flesh. Security forces cordoned off the area and told people to stay away for fear of more blasts.
Two suicide bombers hit the same restaurant in September last year.
In the biggest attack so far this year, al Shabaab in June assaulted the main U.N. compound in the Somali capital, killing at least 22 people.
Somalia has a new elected government that has been in charge for about a year and is striving to rebuild itself after two decades of civil war and lawlessness triggered by the overthrow of President Siad Barre in 1991.
(Writing by George Obulutsa; Editing by Angus MacSwan)