(CNN) -- Security forces clashed with anti-government groups on Saturday in the eastern Syrian city of Deir Ezzor, the state-run SANA news agency and eyewitnesses said.
Security officers and armed protesters fired on one another, SANA said.
At least five people died after security officers fired on protesters and threw hand grenades at houses, said two residents of Deir Ezzor who did not want to be named for security reasons.
The witnesses also said tanks opened fired on two mosque minarets.
"We cannot move between the districts, all neighborhoods have been besieged," one of the witnesses said. "They didn't want to end this until they get all of us."
CNN could not independently verify the reports.
The fighting comes a day after at least 23 people died when government forces cracked down on efforts to get protests under way after Friday prayers, according to activists.
Seven fatalities occurred in the suburbs of Damascus and two in the city itself, six in Deir Ezzor and Boukamal, three in Daraa and one each in Lattakia and Hama, the activists said.
In addition, security forces killed three soldiers when they tried to defect; another 13 were wounded, the activists said.
Syria has been wracked by violent government crackdowns on protests across the country since mid-March, when teens were arrested for writing anti-government graffiti in the southern city of Daraa.
The Syrian Observatory for Human Rights says that since the unrest in the country began, 1,513 civilians had died as of Friday. It put the toll among government forces at 367, not including Friday's fatalities.