Heavy fighting erupted Sunday between Syrian troops and rebels on the outskirts of the capital Damascus, reported an opposition group, dpa reported.
The clashes occurred at a security checkpoint in the suburban area of Kafr Soussa, added the London-based Syrian Observatory for Human Rights. The organization did not give casualty figures.
Several blasts were meanwhile heard in the area of Douma near Damascus, reported the observatory.
The explosions were caused by shelling attacks mounted by Syrian troops against the area, it added.
News from Syria is hard to independently verify, as authorities have barred most foreign media from the country since a popular uprising started against the regime of President Bashar al-Assad in March 2011.
The persistent violence is increasingly dimming chances for the success of a peace plan proposed by the United Nations-Arab League envoy Kofi Annan.