Somalia truck bomb targets Mogadishu's SYL Hotel
A truck bomb has exploded outside a hotel in Somalia's capital, Mogadishu, killing 22 people in a heavily secured area close to the presidential palace.
A BBC reporter says politicians are among the injured.
The Islamist al-Shabab group, which is affiliated to al-Qaeda, says it is behind the attack.
The Somali Youth League (SYL) Hotel is a popular meeting place for government officials and has been targeted by militants before.
A security conference was under way at the hotel on Tuesday morning at the time of the blast.
"Security forces tried to stop the bomber who used back roads before he sped through checkpoints near the presidential palace and detonated the bomb," the Associated Press news agency quotes police officer Col Ali Nur as saying.
"He reached near the gate of the state house with flat tyres."
The BBC's Ibrahim Aden in Mogadishu says politicians and journalists are among people being treated at the city's main Medina Hospital.
Dr Abdulkadir Haji Aden, head of Mogadishu's ambulance service, told the BBC that 22 people had died in the hotel blast and more than 30 were injured.
Al-Shabab is fighting to oust Somalia's UN-backed government and establish an Islamic state.
It was forced out of Mogadishu five years ago by African Union (AU) and government troops, but has continued to carry out bombings in the city.
The group appears to be stepping up its attacks ahead of planned elections in Somalia, with a president due to be elected by MPs in October.
The UK's Foreign and Commonwealth Office condemned the latest attack in Mogadishu.
Minister for the Middle East and North Africa, Tobias Ellwood, said Somalia needed support in the fight against extremism.
"This attack and those like it, such as the suicide bombings in Galkayo on 21 August and last week's attack at Lido beach, only strengthen our determination to work with the Somali people," he said.