Thirty-eight Syrians were killed on day, including 10 shot dead in Baba Amr after regime forces overran the rebel district of the central city of Homs, a watchdog said.
Rami Abdel Rahman, head of the Syrian Observatory for Human Rights, said that 10 Syrians were "shot dead" in Baba Amr, but added: "The circumstances of their deaths are not clear."
The Britain-based watchdog said regime forces had turned a Baba Amr shopping centre into a detention area, and called on the International Committee of the Red Cross, which has a relief convoy poised to enter the neighbourhood, to inspect it.
The Observatory warned of summary executions in Baba Amr after regime troops seized it on yesterday following what rebel fighters called a tactical withdrawal.
Elsewhere in Homs province, 12 people were killed, including five children, when a rocket struck a demonstration as the mostly rebel-held Rastan city was subjected to shelling and heavy gunfire by forces loyal to President Bashar al-Assad.
In Idlib province in the northwest, meanwhile, security forces shot dead a young man at a checkpoint near Maaret al-Numan, the Observatory said. A couple and their driver were also killed when regime forces fired on their car at a bridge in the Idlib town of Saraqeb, it added.
Six civilians were shot dead by security forces in the eastern city of Deir Ezzor, the watchdog added, while three more were killed in Aleppo as security forces opened fire in the Sukari and Masakin Hanano districts.