Syrian security forces on Monday stormed areas near the capital Damascus, in a hunt for army defectors and anti-government protesters, according to activists dpa reported
"House- to- house searches are being carried out in the area and more than 50 have been arrested," Omar Idlibi, a Syrian activist based in Lebanon, told dpa.
Meanwhile, Syrian forces shelled areas in the restive province of Homs following overnight protests against the regime of President Bashar al-Assad.
Around 40 were killed by security forces across Syria on Sunday, according to Idlibi.
On Sunday, the Arab League imposed sweeping sanctions on Syria, including a travel ban on senior officials, after Damascus failed to comply with a peace plan to end its crackdown on protests.
According to the United Nations, at least 3,500 people have been killed since Syrians first took to the streets some eight months ago to demand political change.