(CNN) -- A 12-year-old boy was killed on Sunday when Syrian soldiers fired at a crowd in the city of Homs, according to Rami Abdul-Rahman, director of the Syrian Observatory for Human Rights.
Abdul-Rahman, who is not in Syria but is in contact with activists and protesters there, said several people were killed and wounded.
The Syrian government, meanwhile, reported the deaths of three soldiers and three security officers during clashes with "armed terrorist groups" in the Daraa, Homs and Banias regions.
It said "terrorists" were killed and wounded, scores of them were arrested, and weaponry was confiscated, according to the state-run Syrian Arab News Agency.
Protests have raged for weeks across Syria, one of several outpourings in the Arab world by demonstrators demanding political freedom.
Homs has been one of the cities where security forces of the Bashar al-Assad regime have clashed with peaceful protesters. The regime has said many of its security forces have died in violence it attributes to armed groups.
The fighting continued again on Sunday when residents attempted to stop troops from entering two neighborhoods there and the soldiers opened fire, Abdul-Rahman said.
The violence follows a day of mourning in Homs when thousands took to the streets in funeral processions for seven protesters killed there during the countrywide demonstrations on Friday.
Security forces and army units were present along Homs' main thoroughfares and city gates but did not interfere in the funeral procession, according to a witness who did not want to be identified for security reasons.
After the funerals, Homs was deserted with shops shuttered and people too frightened to leave their homes.
Demonstrations have broken out across provinces and cities in Syria since mid-March, with security forces relying heavily on the army and the regime's guard to disperse demonstrations.
CNN has not been granted access into Syria and is unable to independently verify witness accounts.
But CNN has spoken with witnesses, some of whom have posted homemade videos and reported what they see via social networking sites.
Amnesty International said Friday that more than 540 people have been killed by Syrian security forces and that many activists in pro-reform protests "have been forced into hiding after receiving threats from Syrian authorities."