The crowd unusual because it was dominated by women and young children demanded release of hundreds of men who have been rounded up in the northeastern villages of Bayda and Beit Jnad and surrounding areas in recent days.
"We will not be humiliated!" the crowd shouted Wednesday, according to witnesses who spoke on condition of anonymity for fear of reprisals. They were gathering along the main road between the coastal cities of Tartous and Banias.
Protests erupted in Syria almost one month ago and have been growing steadily, with tens of thousands of people calling for sweeping reforms. President Bashar Assad's government has responded both with brute force and promise of reforms.
More than 200 people have been killed during the unrest, according to Syria's leading pro democracy group, the Damascus Declaration.
In an apparent attempt to calm the women's demonstration, authorities released about 100 of the detainees and brought them to the area where the women were gathered, prompting cheers and cries of triumph, a witness said. The witness, who asked not to be identified for fear of reprisals, said the sit-in will continue until all the men are released.
"Yesterday they raided our home in Bayda and took away my father," said a 21 year old woman. "I'm not leaving here until they return him to us."
Also Wednesday, activists said hundreds of student protesters gathered at Damascus University in the capital and in Aleppo University in the country's north.
Another protest was reported outside the state run news agency's offices in the capital.
The reports lacked detail and could not be independently confirmed because Syria has expelled most foreign reporters and limits access to trouble spots.
Syria's state run news agency acknowledged the student protests for the first time, saying a total of about 50 students staged protests at Damascus University and in the Aleppo campus. It said other students chanted national slogans that reject chaos and attempts to destabilize Syria.
Assad blames the violence on armed gangs rather than reform-seekers and has vowed to crush further unrest.
In contrast, he has made overtures to try to ease growing outrage, including dismissing his Cabinet, firing local officials and granting Syrian nationality to thousands of Kurds, a long-ostracized minority.
The gestures have failed to satisfy protesters who are demanding political freedoms and an end to the decades-old emergency laws that give the regime a free hand to arrest people without charge.
Details about what happened in recent days around Bayda and Beit Jnad were sketchy because the Syrian government has placed severe restrictions on the media and has expelled reporters, including journalists from The Associated Press.
Residents and activists said hundreds of men, young and old, were arrested Tuesday when security forces and pro-government gunmen attacked the villages in northeastern Syria in a move to crush growing dissent there.
Witnesses and members of the Syrian opposition said security forces fired automatic rifles in the two villages. A witness told the AP on Wednesday that at least one person was killed and hundreds of others detained.
Several activists confirmed the death.
The Syrian government countered that a group of "criminal killers" attacked security forces and opened fire indiscriminately in Banias and surrounding areas Tuesday, killing a number of civilians.
The state-run news agency SANA said security forces enlisted the army's help to chase the criminals out of residential areas.
One soldier was killed and two soldiers and six policemen were wounded, the report said. Three members of the armed group were also killed and eight wounded. Some were arrested, it added.
The detentions of protesters, apparently including teenagers, have enraged residents. The witness said security forces forced the men to chant pro-Assad slogans. The accounts could not be independently confirmed.
The two villages are several miles (kilometers) from the port city of Banias, which the army has sealed off during days of unrest. Security forces killed four protesters in Banias on Sunday. The electricity in Bayda appeared to have been cut.
Friday marked the single bloodiest day of the uprising, when 37 were killed around the country.
Also Wednesday, the Syrian government denied a Human Rights Watch charge that Syrian forces prevented ambulances from reaching the wounded Friday in the southern town of Daraa and in Harasta, near Damascus.
An Interior Ministry statement said unidentified gunmen shot at people and prevented ambulances from transporting the wounded to hospitals.
State run television aired what it said were confessions by three members of a "terrorist cell" Wednesday, saying they received money and weapons from a Lebanese lawmaker to instigate protests in Syria and create chaos across the country.
The lawmaker, Jamal Jarrah, laughed off the Syrian aired confessions and denied any involvement. His Future Movement bloc also denied the claims, saying it had no direct or indirect involvement in events in Syria.