Thousands of Syrians have poured into streets across the country with renewed calls for the president's resignation, as the government widens its crackdown on dissent.

Witnesses and activists say anti-government rallies got underway on Friday in cities including Homs, Daraa, and Latakia as well as near the capital, Damascus. There are scattered reports of security forces opening fire on demonstrators who reportedly sustained casualties.

Earlier Friday, security forces mounted new assaults in the country's restive northwest, sending tanks and troops into two more cities.

Rights activists and witnesses say the military sent large numbers of soldiers into Maaret al-Numaan, a city that is on the highway linking the capital and the large city of Aleppo. In addition, the security forces moved into the town of Khan Sheikhun.

Meanwhile, Turkish officials say the number of Syrians who have crossed the border to flee from the unrest is nearing 10,000. The al-Jazeera television network said Friday that some Syrians who have gathered near the Turkish border also demonstrated against President Bashar al-Assad.

World powers are increasingly condemning the crackdown. On Friday, French officials voiced support for additional European Union sanctions on President Assad's regime.

On Thursday, United Nations Secretary-General Ban Ki-moon called on the Syrian president to “stop killing people” and negotiate with the protesters “before it's too late.”

Rights activists and witnesses say more than 1,300 civilians and 340 government troops have been killed since mid-March.