Fighting between rebels and loyalist forces raged in two Damascus neighbourhoods on Tuesday while shelling of a village near the Syrian capital left four members of a family dead, a watchdog said.
"Fierce battles broke out in the Barzeh district of northern Damascus. Shelling in the area wounded five people and caused material damage," said the Syrian Observatory for Human Rights.
The monitoring group later said at least seven people had been killed in the neighbourhood, one by a sniper and the others in shelling.
"Clashes also raged in the outskirts of Jobar (in eastern Damascus), next to Abbasiyeen Square," it added, referring to one of the capital's main squares.
Violence has escalated in Damascus in recent weeks as the army battles to push back insurgents seeking to penetrate the capital from enclaves on its outskirts.
Shelling on Al-Hajar Al-Aswad in southern Damascus killed at least three men and wounded more than 20 civilians, the Observatory said.
In Mqailyabeh in Damascus province, large swathes of which are under insurgent control, army shelling killed a three-year-old boy, his five-year-old sister, their mother and grandmother, the group added.
Elsewhere in the country, the Observatory said gunmen loyal to the Syrian regime had kidnapped passengers from a bus carrying residents of the town of Maaret Masrin, in the northern province of Idlib.
The Observatory -- which relies on a broad network of activists, doctors and lawyers for its reporting -- said at least 78 people had been killed so far on Tuesday.
A day earlier it announced that March was the deadliest month in Syria's two-year conflict, according to its count, with more than 6,000 people killed.
The UN says more than 70,000 people have been killed since March 2011, when a protest movement broke out against President Bashar al-Assad.
The peaceful movement spiralled into an insurgency after the army unleashed a brutal crackdown on dissent.