Activists say at least three people were killed by Syrian forces as tens of thousands took to the streets nationwide in protest of a continuing crackdown by the regime of President Bashar al-Assad.

The Syrian Observatory for Human Rights says the three died a military incursion early Friday in the Jabal al-Zawiya region near the Turkish border.

The deaths and Friday protests come as U.S. Secretary of State Hillary Clinton says time is running out for the Syrian government.

Clinton made the comments Friday at the “Community of Democracies'' gathering in Lithuania's capital, Vilnius. She said the government must make genuine reforms or face increased resistance.

Clinton also said Mr. Assad's efforts to reach out to the opposition through one meeting earlier this week was not “sufficient.” She added that allowing an opposition meeting in Damascus while deploying tanks in the north was not sending a coherent message.

Syria has continued a brutal crackdown on anti-government protesters calling for the president to step down. In the latest violence, security forces killed at least 12 people in two days during an ongoing military operation near the Turkish border in the country's northwest.

Pro-government forces also appeared to be preventing residents in recent days from crossing into Turkey, where more than 12,000 Syrians have fled to escape the violence in their homeland. Hundreds more Syrian refugees have left for Lebanon.

Turkish officials said only five Syrians made it across the border Thursday, the lowest number in days.

Details of events in Syria are difficult to independently confirm because the government allows very few foreign news reporters into the country and restricts their movements.

Rights groups say more than 1,400 people have been killed in the violence, most of them unarmed protesters.