At least 95 people have been killed in shelling and firefights between government troops and army defectors in Syria, according to reports.
The deaths on Saturday were reported from the cities of Homs, Hama and Aleppo by Syrian opposition groups and Al Jazeera sources.
The town of Taftanaz within the flashpoint province of Idlib also came under attack.
The Local Co-ordination Committees activist network said on Saturday that at least 24 people were killed in the village of al-Latamneh in the suburbs of the city of Hama.
The British-based Syrian Observatory for Human Rights put the al-Latamneh death toll at 27.
The group said most of those people were killed by shells fired as troops tried to storm al-Latamneh after clashes with defectors there over the past two days.
Farther to the south, at Qusayr in central Homs province, three civilians were killed, including a woman, a child and a defector from the police, said the UK-based activist group.
At least 77 people were killed across Syria on Thursday and 35 on Friday, most of them civilians, according to figures by the Syrian Observatory.
Ban Ki-moon, the UN secretary-general, on Friday sharply criticised the Syrian government for its latest attacks on civilians, saying that increased attacks by government forces on Syrian cities "violate" the UN Security Council's demand for an end to hostilities.
The UN press office said in a statement that the secretary general believes that Syrian President Bashar al-Assad is using an April 10 deadline to pull troops and heavy weapons away from cities as "an excuse" to step up killing.
"[Ban] strongly condemns the latest escalation of violence," the statement said.
The UN statement continued: "He deplores the assault by the Syrian authorities against innocent civilians, including women and children, despite the commitments by the government of Syria to cease all use of heavy weapons in population centers.
"The 10 April timeline to fulfill the government's implementation of its [ceasefire and troop withdrawal] commitments, as endorsed by the Security Council, is not an excuse for continued killing.
"Such actions violate the consensus position of the Security Council" which backed the peace plan drawn up by UN-Arab League envoy Kofi Annan and the April 10 deadline he agreed with Assad.
"The Syrian authorities remain fully accountable for grave violations of human rights and international humanitarian law," Ban's statement said. "These must stop at once."
In another development, the US released satellite images on Friday it said showed Syria has artillery poised to hit residential areas and has deployed forces to towns and cities despite calls for a withdrawal.
Robert Ford, the US ambassador to Syria, posted the images on the internet website Facebook in what seemed an effort to pressure Assad to pull back forces as called for in the peace plan.
"This is not the reduction in offensive Syrian government security operations that all agree must be the first step for the Annan initiative to succeed," Ford said on Facebook.
Ford, who left Damascus when the US embassy was closed in February, said the images showed the withdrawal of tanks from Dael in Deraa province as well as from Taftanaz, a village east of Idlib city in Idlib province.
Ford said "the Syrian government simply moved some armoured vehicles out of Taftanaz to the nearby town of Zirdana".
Other images carried arrow markings and a caption that said the Syrian government had "kept artillery units near residential areas" such as in Homs and Zabadani "where they could again fire upon them".