At least 21 civilians were killed by security forces in Syria on Wednesday, the Syrian Observatory for Human Rights said in a statement, raising its earlier death toll from five.
"Twenty-one civilians were shot dead by the military and security forces across Syria, among them 11 in the Hama region" 210 kilometres (130 miles) north of Damascus, the Britain-based group said.
"The Hamidiyeh district of Hama was targeted by heavy machineguns, and clashes between deserters and regular soldiers are continuing" in the area, it said.
Farther south in Homs, security forces using machineguns killed five civilians in areas including Bayyada and Baba Amro.
In the northwest province of Idlib near along the border with Turkey on Wednesday, security forces shot dead three civilians at Maar Misrin, the Observatory said.
It also said snipers shot dead an Iraqi woman at Zabadani in Damascus province.
A civilian was also killed in Lujat village in the southern province of Daraa, cradle of the uprising, amid clashes between deserters and security forces.
Another four people were also reported to have died in Homs province, either "from torture or wounds received previously."