'Attacker' arrested as bomb blast rocks Syrian capital Damascus

A "terrorist" has been arrested after a huge explosion in Damascus, Syrian state media has said, in a rare attack in the capital, which has been largely insulated from violence over the past year.

State news agency SANA said that a "bomb blast" near a highway at the southern edge of the city had caused the explosion "without leaving any victims".    

"There is confirmation of reports that a terrorist has been arrested," it said

Earlier, the head of the city's civil defence, Asef Hababe, told the Reuters news agency the blast on Sunday came from military technicians detonating a bomb.

A UK-based activist group said that some people had been killed and injured in the blast.

"The explosion took place near a security branch in the south of the city," the Syrian Observatory for Human Rights told the AFP news agency.

"There are some people killed and injured, but we could not verify the toll immediately."

It said that shooting followed the explosion.

Syria is locked in a civil war that has killed more than 360,000 people and displaced millions since a brutal crackdown on anti-government protests in 2011 spiralled into full conflict.

With key military backing from Russia, President Bashar al-Assad's forces have retaken large parts of Syria from various armed groups, and now control almost two-thirds of the country.

The Syrian regime in May reclaimed a final scrap of territory held by the Islamic State in southern Damascus, cementing total control over the capital for the first time in six years.

Observatory chief Rami Abdel Rahman said that Sunday's blast appeared to be the first attack in Damascus in over a year.