Activists say Syrian troops are shelling districts in a suburb of the capital Damascus, causing casualties.

The Local Coordination Committees activist network says explosions shook Douma early Sunday as troops stormed neighbourhoods in the sprawling suburb, the scene of clashes between rebels and security forces before a ceasefire went into effect a week ago.

Douma-based activist Mohammed Saeed said tanks were shelling parts of the suburb. He says two people were killed, but that could not be immediately confirmed with other activist groups.

The Security Council approved a resolution Saturday expanding the U.N. ceasefire observer mission. A smaller team is already in the country and has been touring flashpoints.

The Syrian Observatory for Human Rights, a Britain-based opposition group with a network of activists on the ground, confirmed the deaths. It also reported that a third person was killed overnight in the village of Hteita outside Damascus when troops opened fire from a checkpoint.

It was not immediately clear what prompted the attack on Douma. Mr. Saeed said loud explosions that shook the city early Sunday caused panic among residents, some of whom used mosque loudspeakers to urge people to take cover in basements and in lower floors of apartment buildings.

“This U.N. observers thing is a big joke,” Mr. Saeed said. “Shelling stops and tanks are hidden when they visit somewhere, and when they leave, shelling resumes.”

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