The Arab League has called for "immediate change" in Syria, urging President Bashar al-Assad to end the government's violent crackdown on dissent and launch a comprehensive national dialogue.
Arab foreign ministers meeting in Cairo Tuesday demanded that Syrian authorities implement measures agreed upon during a visit to Damascus last week by the league's secretary-general.
Qatar's foreign minister Hamad bin Jassim al-Thani, who chaired the meeting, said the the current situation remains critical and that Syria must stop what he called its "killing machine."
Also Tuesday, Turkey's prime minister told the Egyptian newspaper Al-Shorouk that he fears the crisis in Syria could descend into a sectarian civil war between the Alawites and the Sunnis.
Syria's ruling elite belong to the minority Alawite sect - an offshoot of Shi'ite Islam - while most of the country's citizens are Sunni Muslim.
In separate comments before several thousand people in Cairo, Erdogan said civilian deaths have increased in Syria, but reforms have not followed. He said that neither the Syrian people nor the Turkish government believe anymore in Assad.
Earlier Tuesday, activists said Syrian security forces carried out sweeping arrests and raids in areas outside the capital, Damascus, and in a string of cities including Daraa, Latakia and Banias.
Demonstrators also burned Russian flags in the flashpoint cities of Homs and Daraa to protest Moscow's support for Assad. Both Russia and China oppose a draft U.N. Security Council resolution backed by European nations and the U.S. that would impose an arms embargo and other sanctions on Syria.
The United Nations estimates that 2,600 people have been killed in Syria's six-month-long uprising.
An aide to Assad disputed the U.N. figures Monday, saying that 1,400 have died. A Syrian government spokesman said the casualties have been evenly split between government forces and opposition activists.