The leader of the military wing of an Islamist insurgent organisation in Somalia has been killed in an overnight air strike.
Aden Hashi Ayro, al-Shabab's military commander, died when his home in the central town of Dusamareb was bombed.
Ten other people, including a senior militant, are also reported dead.
A US military spokesman told the BBC that it had attacked what he called a known al-Qaeda target in Somalia, but refused to give further details.
Al-Shabab, considered a terrorist group by the US, is the military wing of the Somali Sharia courts movement, the Union of Islamic Courts (UIC), until Ethiopian troops ousted them in 2006.
The group has since regrouped and is in effect in control of large parts of central and southern Somalia.
An al-Shabab spokesman, Mukhtar Robow Adumansur, told the BBC that Ayro was killed along with another militant commander in the attack.
Locals said it happened at about 0300 (0000 GMT).
"We heard a huge explosion and when we ran out of our house we saw balls of smoke and flames coming out of house," Dusamareb resident Nur Geele told the BBC.
"The house was totally destroyed to the ground, also other houses nearby," local elder Ahmed Mumin Jama said.
Dr Ahmed Mahdi at Dusamareb Hospital told the BBC's Somali Service that he was treating eight civilians, including women and children, for burns and shrapnel wounds.
One of the women has since died, bringing the death toll so far to 11.
He said identifying the dead would prove difficult as the al-Shabab villa and surrounding mud houses and trees were now scorched earth.
Ayro received training in Afghanistan in the 1990s and was an instrumental military figure as the UIC took control of Mogadishu in the second half of 2006, says the head of the BBC's Somali Service Yusuf Garaad.
The US says al-Shabab is part of the al-Qaeda network, although correspondents say it is impossible to accurately establish those links.
Al-Shabab leaders say it is a purely Somali movement and they deny any involvement with al-Qaeda.
'No longer safe'
Mr Robow warned that there would now be revenge attacks by the al-Shabab.
"This incident will cause a lot problems to US interests in the region and the governments who support the US, by that I mean its allies who are puppets," he said, referring to Ethiopia which backs Somalia's interim government.
"I am letting the citizens of the US and the allies know they are not going to be safe in this area."
In its annual report on terrorism published on Wednesday, the US said al-Shabab militants in Somalia, along with al-Qaeda militants in east Africa, posed "the most serious threat to American and allied interests in the region".
Al-Shabab has been at the forefront of a guerrilla insurgency against the government and its Ethiopian allies since early 2007.
In recent weeks, they have briefly captured several towns in central and southern Somalia before withdrawing.
The US has launched several air strikes against suspected extremist targets in Somalia in recent months.
It has an anti-terror task force based in neighbouring Djibouti, and has accused Somali Islamists of harbouring those responsible for the 1998 attacks on its embassies in Kenya and Tanzania.
The Islamists denied this.
Somalia has not had an effective national government since 1991.