Syrian police have disrupted a rare protest by human rights activists demanding political and civil reforms.
Syrians in London protested outside the country's embassy
At least 30 arrests were made during a sit-in before the Damascus parliament building, says a Syrian rights group.
The protest marks the 41st anniversary of the day Syrian Baathists seized power, declaring a state of emergency.
The BBC's Kim Ghattas in Damascus says the exact number of protesters was hard to establish, as their ranks were heavily infiltrated by police agents.
The protest against the emergency laws in place for 41 years was organised by rights group, the Committees for the Defence of Democratic Liberties and Human Rights in Syria.
The group has also been circulating a petition urging President Bashar al-Assad to release political prisoners and lift the state of emergency.
Several local and foreign journalists at the scene were also briefly put under arrest but were later released, say media sources in Beirut.
Organisers had been summoned by state security for questioning several times in recent days.
However they said on Sunday they would not be intimidated.
Monday saw riot police standing guard and the demonstrators were outnumbered intelligence officers in civilian clothes and black leather jackets.
One man raised a banner reading "Freedom for Prisoners of Opinion and Conscience" - but it was quickly torn up by agents, the Associated Press reported.
Assad: Under growing pressure to implement political reforms
About 20 minutes into the protest, the main organiser, Aktham Naisse, was detained along with several others.
A Paris-based spokesman for the protest's organisers told Arabic television station al-Jazeera that the campaign for reform was a purely domestic issue for Syria.
"We categorically refuse any foreign pressure, particularly the US pressure [for action against Syria] which we condemn," Ghayyath Naisse said.
"At the same time, we do not believe that the call for reform, which was initiated three years ago, should be disregarded."
Syrian flags and large banners hailing President Assad's leadership have been put up on the streets of Damascus to mark the coup which brought the Baath Arab Socialist Party to power.
But official festivities are expected to be limited and low-key.
Observers say there is a feeling there is not much to celebrate and that officials are still painstakingly trying to avoid parallels between Syria and Iraq.
In Iraq, the Baath party - which also came to power in 1963 - was led by Saddam Hussein who was ousted as president almost a year ago.