Syrian troops and rebels were clashing in a Palestinian refugee camp in the capital Damascus, activists said Tuesday.
They also said that fighter jets have resumed attacks on the northern province of Idlib and suburbs of the capital. Tuesday's airstrikes come a day after activists reported the most widespread bombing in a single day since Syria's 19-month crisis began.
The Britain-based Syrian Observatory for Human Rights and the Local Coordination Committees said that fighting in the Yarmouk refugee camp broke out after midnight. They had no word on casualties.
Palestinian refugees in Syria tried to stay on the sidelines when the uprising against President Bashar Assad began in March. But many Palestinian youths have joined the fight as they became enraged by mounting violence and moved by Arab Spring calls for greater freedoms.
Palestinians have largely stayed out of the war in Syria between Assad's security forces and rebels trying to topple the government. Leaders have sought to avoid commenting on the situation and embroiling their exiles.
Syria is home to nearly 500,000 UN-registered Palestinians, and their descendants, who were expelled or fled from their homes during the 1948 war of Israel's creation. Palestinians say an additional 120,000 Palestinians reside in Syrian cities.
Palestinians in Gaza and the West Bank staged several rallies in past months against Assad's regime.
Syria's civil war, which had raged across much of the country, came to the capital and northeastern city of Aleppo, Syria's main commercial hub in July.
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