Syrian authorities arrested a popular opposition figure hours after passing a bill lifting nearly 50 years of emergency rule.
Rights activists say Mahmoud Issa was taken from his home in the central city of Homs late Tuesday by Syria's political security services.
Earlier in the day, the government has passed a bill ending emergency rule, dissolved a security court that tries political prisoners and passed legislation requiring permits for demonstrations.
A U.S. State Department spokesman says Washington is concerned Syria may have replaced one restrictive law with another. He urged Damascus to put broader democratic reform in place.
Despite the new legislation, thousands of demonstrators gathered in cities and towns across the Syria Tuesday to protest the regime of President Bashar al-Assad. At least two people were killed during clashes in Homs where protesters held a sit-in in the cities main square.
Syrian authorities often have said their country is the target of a conspiracy. They blame the violence on armed gangs and infiltrators supplied with weapons from Lebanon and Iraq.
Syria has been ruled by the Assad family since 1970, when the current president's father, Hafez al-Assad, became head of state. He died in 2000, leaving Bashar al-Assad to lead the country.
Syria's emergency law banned demonstrations, restricted the media and allowed eavesdropping.