Syrian forces have renewed their assault on Homs, bombarding more areas of the central city, activists say, with aid agencies still unable to gain access to neighbourhoods in desperate need of relief.
Sunday's bombardment of Syria's third-largest city with about one million inhabitants came as China offered a proposal to end the violence in the country, calling for an immediate ceasefire and talks by all parties but standing firm against any intervention by outside forces.
Syrian artillery gunners also pounded the mainly rebel-held city of Rastan in the centre of the country on Sunday, monitors said.
Four children were said to be among seven civilians killed in the shelling. The victims included six family members killed when a rocket slammed into their home, said the London-based Syrian Observatory for Human Rights which reported intensive shelling of Rastan since daybreak.
Conditions in the western Homs neighbourhood of Baba Amr have been described as catastrophic, with reports on Saturday speaking of extended power outages, shortages of food and water, and no medical care for the sick and wounded.
Government forces took control of the opposition stronghold on Thursday after opposition fighters fled under the same constant bombardment that activists said killed hundreds of people since early February.
The Syrian government has said it is fighting "armed gangs" in Baba Amr and has pledged to "cleanse" the neighbourhood.
Al Jazeera's Sue Turton, reporting from Beirut in neighbouring Lebanon, said the UN and international rights groups were investigating the government's crackdown in the area.
Many locals were wondering where the next government offensive will take place, she said.
"Shelling is now going on in a different neighbourhood of Homs," she added.
"Many believe the same 'cleansing' of Baba Amr, as the army is calling it, is going to be carried out in areas in the south [of the city], where it is believed many of the Free Syrian Army has gone."
News agencies confirmed that other areas in Homs came under heavy shelling on Saturday, including neighbourhoods where many of Baba Amr's residents had sought shelter.
The Local Co-ordination Committees, an opposition activists' network, said mortars struck the districts of Khaldiyeh, Bab Sbaa and Khader.
Abu Hassan al-Homsi, a doctor at a makeshift clinic in Khaldiyeh, said he treated a dozen people who were wounded, most lightly.
"This has become routine, the mortars start falling early in the morning," he said. Several homes were damaged from the morning shelling, which he described as steady but intermittent.
Another Khaldiyeh resident, who spoke on condition of anonymity for fear of reprisals, said the district has been without water and heating fuel for a week, amid freezing temperatures.
"We are collecting rain and snow water, and cutting trees to burn to warm ourselves," he said.
The International Committee of the Red Cross (ICRC) said earlier this week that it had received permission from Bashar al-Assad's government to enter Baba Amr.
A convoy of seven lorries with 15 tonnes of humanitarian aid including food, medical supplies and blankets left Damascus on Friday, taking several hours in heavy snowfall to reach Homs.
But once they neared Baba Amr, the government prevented them from entering.
"We are still in negotiations to enter Baba Amr," Hicham Hassan, an ICRC spokesman, said on Saturday in Geneva, Switzerland.
Syrian authorities said they were not letting the ICRC into Baba Amr because of safety concerns from land mines and other dangers, Hassan said, adding the organisation had not been able to verify the danger.
The government has not offered its explanation for revoking the permission.
"It's important that we get in today," Hassan said. "We are not about to give up."
On Friday the ICRC reported that it started to distribute aid at a village near Homs but that it had not been allowed access to Baba Amr.
Al Jazeera's Turton said the government may have other motives for keeping the medics out of Baba Amr.
"There have been reports that some sort of government clean-up operation is going on, rounding up men older than 14. There have been reports of imprisonment, torture and even executions [of opposition fighters], and they don't want the ICRC or independent people there, to witness this," she said.
The proposal floated by China is part of renewed efforts by the country to seize the diplomatic initiative in Syria after being criticised by the US and others for joining Russia in vetoing a UN Security Council resolution last month.
China had said the resolution would have opened the door to intervention against the Bashar al-Assad government.
"We oppose anyone interfering in Syria's internal affairs under the pretext of 'humanitarian' issues,'' according to the proposal from an unnamed "leading official'' and posted on the foreign ministry's website.
The proposal later said: "China does not approve of armed interference or pushing for 'regime change' in Syria and believes that use or threat of sanctions does not help to resolve the issue.''
In-depth coverage of escalating violence across Syria
Turkey's foreign minister said a lack of international consensus over Syria was emboldening the government there to proceed with its crackdown.
Ahmet Davutoglu said the scale of the killing matches the bloodshed in the Balkans wars of the 1990s, and described the Assad government's actions as a "crime against humanity".
Davutoglu spoke on Saturday at a joint news conference with his Italian counterpart, Giulio Terzi. Both ministers criticised Syria for blocking the Red Cross convoy.
In another Syria-related development, the bodies of American journalist Marie Colvin and French photographer Remi Ochlik were flown from Damascus to Paris on Sunday. The two journalists were killed in Homs last week during attacks by the Syrian army on the Baba Amr neighbourhood.
Eric Chevallier, the French ambassador, received the body of French photographer Remi Ochlik, and a Polish diplomat received the remains of American Marie Colvin. US interests in Syria are represented by Poland.
Colvin's body was expected to be flown on to the US on Monday or Tuesday, according to a representative of her newspaper, Britain's Sunday Times.
The journalists had entered Syria illegally to report on the government crackdown in the country. They died on February 22 in shelling that also wounded Edith Bouvier, of the French daily Le Figaro, and Paul Conroy, a British photographer.