At least 19 people were killed Wednesday when Syrian security forces stormed rebellious areas in the centre and south of the country, activists based in Beirut told dpa.
"The casualties were mostly in Homs and Idlib," Omar Idlibi, a Syrian activist, said, adding that the death toll in the past two days had reached 34.
The state-run Syrian News Agency SANA said its forces had stormed areas in Homs and Idlib and arrested 14 men whom it described as "armed terrorists."
"The leader of the armed terrorist group that attacked a passenger bus and committed acts of murder, abduction and rape, was also arrested," reported SANA.
The Syrian government has repeatedly accused "terrorist gangs," allegedly financed by foreign countries, of being behind the unrest that has gripped the country since mid-March.
More than 3,500 people have been killed in the violence, according to the United Nations.
The latest violence prompted several Western and foreign embassies to issue warnings for its citizens to leave the country.
The US Embassy in Damascus urged its citizens in Syria to depart "immediately," while Saudi Arabia and Turkey called on its nationals not to travel to Syria.
The Turkish and Saudi warnings came two days after one Saudi national was killed by Syrian security forces fire in Homs region, while two Turkish buses came under fire in the same region, leaving two people wounded.
The intensified Syrian military attacks came a day ahead of Arab League talks in Cairo to discuss the Syrian crisis after the 22-member organization rejected Syrian amendments to its plan to send Arab observers to Syria to protect civilians.
The Arab League suspended Syria's membership over the bloodshed and Syria's failure to abide by an Arab peace plan.