BEIRUT — Syrian protesters called yesterday for a one-day nationwide general strike, urging students to skip school and workers to bring commerce to a halt in a new strategy of defiance against government crackdowns that appear to be turning more brutal and bloody.

The strike, planned for today, marks a shift by opposition forces to strike at President Bashar al-Assad’s regime from new angles: its economic underpinnings and ability to keep the country running during two months of widening battles.

A sweeping popular acceptance of the strike call would be an embarrassing blow to Assad and show support for the uprising in places, such as central Damascus, where significant protests have yet to take hold and security forces have choked off the few that have taken place.

“It will be a day of punishment for the regime from the free revolutionaries . . . Massive protests, no schools, no universities, no stores or restaurants, and even no taxis. Nothing,’’ said a statement posted on the main Facebook page of the Syrian Revolution 2011.

The strike call came as the United States and European Union planned new sanctions against the Syrian leadership. In Washington, US Secretary of State Hillary Rodham Clinton and EU foreign policy chief Catherine Ashton told reporters that the tighter measures could be imposed in the coming days.

Meanwhile, watchdog groups and Syrians fleeing into neighboring Lebanon added to the accounts of violence.

A Syrian rights activist, Mustafa Osso, said government agents chased and beat students taking part in a protest against Assad’s regime at a university in Aleppo. Security officials in Lebanon said at least 170 people entered the country yesterday, including a 2-year-old girl with a shrapnel wound in her chest.

Syrians pouring over the Lebanon border in recent days have described horrific scenes of execution-style slayings and bodies in the streets in the western town of Talkalakh, which has reportedly been encircled by security forces. Osso, head of the Kurdish Organization for the Defense of Human Rights and Public Freedoms in Syria, said there were reports of gunfire in Talkalakh yesterday, but it was not clear whether there were injuries.

At least 16 people — eight of them members of one family — have been killed in recent days in Talkalakh, a town of about 70,000 residents, witnesses and activists said.

Syria’s official news agency said eight soldiers and policemen were killed yesterday and five others were wounded while pursuing fugitives in Talkalakh and nearby areas. The report said security forces arrested several fugitives and confiscated a large amount of weapons.

Syria’s top rights organization has said that the crackdown by Assad has killed more than 850 people since protests erupted in mid-March in the most serious threat to his family’s 40-year dynasty. Thousands of other people have been detained.

A prodemocracy activist in the central city of Homs expressed support for the nationwide strike, calling it “the only way to hurt the regime without putting people’s lives at risk.’’

© Copyright 2011 Globe Newspaper Company.