Syrian tanks "indiscriminately" shelled a residential area on the outskirts of Hama late on Monday, an activist in the flashpoint protest city told AFP by telephone.
The attack came as the UN Security Council was poised to hold an emergency debate on the Syrian government's bloody crackdown on dissent, a day after nearly 140 protesters died across the country, mostly in Hama.
"Ten tanks are shelling Dawar Bilal indiscriminately," the activist told AFP in Nicosia as the booms of explosions were heard in the background, referring to a residential area on the outskirts of Hama.
Rami Abdel Rahman of the Syrian Observatory for Human Rights called Sunday "one of the deadliest days" since pro-democracy protests broke out in Syria in mid-March.
He also said four more civilians were killed on Monday in Hama as security forces carried out raids and search operations, while a boy aged 13 and another person were shot dead in the eastern town of Al-Bukamal.
The head of the Syrian League for the Defence of Human Rights, Abdel Karim Rihawi, told AFP that "intense shooting" was heard across Hama late on Monday, the first night of the Muslim dawn-to-dusk fasting month of Ramadan.
The official SANA news agency said troops were locked in clashes with "saboteurs" in Hama, where activists said 100 people were killed in an army assault on Sunday.
"The army is pursuing its mission in Hama and is removing barricades erected by groups of saboteurs at the entrances of the city," SANA said quoting a military official.
"Right now there are widespread clashes because these groups are well organised and use sophisticated weapons and have planted mines along main streets" in the city, SANA added.
Sunday's crackdown on Hama came on the eve of the start of Ramadan, when observant Muslims break their daily fast by holding an "iftar" meal at dusk.
President Bashar al-Assad on Monday marked the nation's Army Day by showering his troops with praise even as international condemnation swelled ahead of the UN meeting on the crisis.
The Security Council was to hold closed consultations from 2100 GMT, a spokesman for the council presidency said, following demands from European powers to condemn Assad's deadly crackdown.
The army had "proved its loyalty to its people, country and creed," Assad said.
"Its efforts and sacrifices will be admired. These sacrifices succeeded in foiling the enemies of the country and ending sedition, preserving Syria," he said.
The embattled president later the same day visited wounded soldiers convalescing in a Damascus hospital, SANA reported. "All Syrians appreciate the army," he said.
At least 1,583 civilians and 369 members of the army and security forces have been killed since mid-March in Syria, according to the Syrian Observatory.