Syrian forces struck back against rebels today with attack helicopters and shelling in Damascus, one day after an audacious rebel attack in the capital killed three leaders of the regime.

Syrian government forces are shelling a number of neighbourhoods in and around the capital Damascus, anti-regime activists say, a day after a bomb killed three members of president Bashar Assad’s inner circle.

Rebels penetrated the heart of Syria's power elite, detonating a bomb inside a crisis meeting in Damascus that killed three leaders of the regime, including President Bashar Assad's brother-in-law and the Defence Minister Dawoud Rajha.

Syria’s opposition has demanded an independent investigation into the bombing which killed 25 people at a busy Damascus junction, blaming forces loyal to the regime for the atrocity – the second major attack in the capital in as many weeks.

A government crackdown on two Syrian towns in the country’s centre and south killed at least 33 people, including an 11-year-old girl shot dead by troops during a fierce shelling, activists have said.