Police in Belgium say they have detained several Kurds who stormed the the Syrian embassy in Brussels.
The incident comes after 14 people were killed on Friday and Saturday in clashes between Kurds and police in Qameshli in northern Syria.
Some damage was reported to the embassy building, with chairs overturned and windows shattered, police said.
In Syria authorities imposed a curfew in Qameshli, together with the nearby Kurdish towns of Hassakeh and Amuda.
Syria's interior minister has also been sent to the area to take charge of efforts to end the disturbances, Reuters news agency reported.
In Belgium the Syrian ambassador told French news agency AFP that he had asked the authorities to step up security around the embassy premises following the incident.
Trouble flared on Friday, when nine people were killed and more than 100 injured in fighting at a premier league football match in Qameshli.
A shouting match had erupted between Syrian Arabs and Syrian Kurds at the match - involving the al-Fatwa and al-Jihad teams - when police intervened.
Six people were shot dead and three others - thought to be children - were crushed to death in the ensuing stampede.
A further 100 people were injured, hospital officials said.
Witnesses said there were between 5,000 and 7,000 spectators at the game.
Some of the 2,000 visiting fans threw sticks and stones at the home supporters, they said.
One witness said: "We had nothing to defend ourselves with because we were not expecting this so we had to run and there was a stampede."
On Saturday five people were shot dead by police in Qameshli as rioters protested at the funerals of those killed the day before.
Mourners shouted anti-government slogans and attacked shops and government buildings, setting fire to a department of customs office, according to one witness.
Police fired shots into the air to disperse crowds trying to protest in the main street, another witness said.
There were also minor disturbances in the capital, Damascus, where several Kurds reportedly blocked a road and damaged several cars before being dispersed by riot police.
This is a rare outburst of popular anger and violence in the tightly controlled Syrian state and is a sign of growing Kurdish discontent, says the BBC's Kim Ghattas.
Syria's Kurds have no say in politics and no social or cultural rights.
Syria fears the creation of a Kurdish state which would threaten its territorial unity.