At least 50 civilians have reportedly been killed in fresh Syrian government attacks on the besieged rebel-held Eastern Ghouta region outside Damascus.
First responders from the Syria Civil Defence said air and artillery strikes on the town of Marj left 24 dead there.
A monitoring group said 127 civilians were killed on Monday in the deadliest day for three years in the enclave, where some 393,000 people are trapped.
The UN has warned that the situation there is "spiralling out of control".
It has said the indiscriminate bombardment of the Eastern Ghouta must stop immediately and called for a ceasefire to allow humanitarian aid to be delivered and hundreds of critically sick and wounded patients to be evacuated.
What's happening on the ground?
Activists said at least 10 towns and villages across the region came under renewed bombardment by the Syrian government and its allies on Tuesday.
The Syria Civil Defence, whose rescue workers are commonly known as the White Helmets, said five women and children were among the 24 people killed in Marj. Another 10 civilians died as a result of strikes on Arbin and Misraba, it added.
The Local Co-ordination Committees, an opposition activist network, reported that 77 civilians had been killed, while the Syrian Observatory for Human Rights, a UK-based monitoring group, put the death toll at 50, including 13 children.
It said 194 people had now been killed and 850 wounded since the government bombardment intensified on Sunday night.
Syrian state television meanwhile reported that at least two people living in government-controlled areas of eastern Damascus were killed and 13 others wounded by shells fired by rebels based in the Eastern Ghouta.
The Syrian military has not commented on the reports from the Eastern Ghouta, but said it carried out "precision strikes" on areas from which the shells were launched.
