At least 15 people were killed, and 20 others were wounded in an explosion at a restaurant in Beledweyne in central Somalia on Saturday, Somali state TV reported.

Somali's Prime Minister Mohammed Roble conveyed his condolences to the victims' families. 

Abdirahman Keynan, the deputy district Commissioner for Social Affairs, was among the victims of the explosion, who were primarily civilians.

Police and state officials confirmed the attack was caused by a suicide bomber but did not give the number of casualties.

According to witnesses who spoke to AFP, the blast occurred in an open area of the Hassan Dhiif restaurant where people had gathered under trees to eat lunch and enjoy the breeze.

"This was the deadliest attack I can recall in this town," a local police officer, Mohamud Hassan, told AFP.

Al-Shabaab, an al-Qaeda-affiliated terrorist group, has claimed responsibility for the attack, according to a report by SITE intelligence, which monitors militant groups online.

Al-Shabaab has also previously claimed responsibility for a series of recent attacks in the Horn of Africa nation.

The attack comes at a time when Somalia is conducting parliamentary elections which are supposed to conclude on February 25.

Prime Minister Mohammed Roble conveyed his condolences to the victims' families.

Meanwhile, two people were killed and five others wounded in a bomb attack which targeted a tea shop in Bosaso town in Puntland State, also on Saturday.

(With input from agencies)