|At least five people were killed in Homs as hundreds protested against the rule of Syrian President Bashar al-Assad
Syria's opposition has appealed for international intervention in the central city of Homs, one of the focal points of the country's uprising, calling it a "humanitarian disaster area".
The appeal, issued by the Turkey-based Syrian National Council, came as activists reported that at least 11 people were killed across the country on Monday, including two children, in an ongoing crackdown on anti-government protesters by security forces.
Al Jazeera's Rula Amin reports on the situation in the central city of Homs
Activists said that at least eight of the dead were in Homs where hundreds of residents protested against the rule of Syrian President Bashar al-Assad, adding that government troops stormed several areas and made house-to-house arrests.
Heavy artillery clashes erupted between regime forces and presumed army defectors in Homs, activists reported, saying it was the fifth day of a "brutal siege on the brave city".
Al Jazeera's Rula Amin, reporting from neighbouring Lebanon, said: "People there are trying to tell the government that they will not succumb and they will continue to protest until they topple the regime...despite the heavy presence of the security forces."
More than 110 people have been killed in the past week in Homs, Syria's third-largest city, according to the Local Co-ordination Committees activist network.
'Stop the massacre'
The Syrian Observatory for Human Rights said the heavy artillery clashes in Homs left "dozens of dead and wounded in both camps".
"Shooting could be heard in Homs where neighbourhoods came under heavy machinegun fire at dawn," the UK-based rights group said, adding "more than 40 explosions were heard".
In-depth coverage of escalating violence across Syria
In a statement, the Syrian National Council urged the United Nations, the Organisation of Islamic Co-operation and the Arab League to act "to stop the massacre committed by the regime".
It also called on the international community to send "Arab and international observers, instantly, to the city of Homs to oversee the situation on the ground, and prevent the regime from continuing to commit brutal massacres".
The Arab League has called for a meeting to be held next Saturday in Cairo to discuss Syria's failure to implement a peace plan previously announced by the body following talks with Syrian officials.
The League said that the meeting was called because of "the continuation of violence and because the Syrian government did not implement its commitments in the Arab plan to resolve the Syrian crisis".
In another development, Walid al-Moallem, Syria's foreign minister, criticised the United States for urging suspected gunmen to not hand over their weapons to authorities under an amnesty offer, Syrian state media reported on Monday.
"Syria considers the US call an encouragement for the armed groups to pursue their criminal acts against the Syrian people and state," state television quoted Moallem as saying.
According to reports, Moallem made the criticism in letters to his counterparts in Russia, China, India, South Africa, Brazil and the Arab League.
On Friday, the Syrian government announced details regarding a week-long amnesty period to begin on Saturday, calling on "citizens who carried weapons, sold them, delivered them, transported them or funded buying them, and did not commit crimes, to hand themselves into the nearest police station".
"The interior ministry assures that those who turn themselves in...will then be freed immediately and it will be considered a general amnesty," state media said.
However, in a press briefing in Washington DC, Victoria Nuland, US State Department spokesperson, advised Syrians against turning themselves in.
"I wouldn't advise anybody to turn themselves in to the regime authorities at the moment," she told reporters.
In other parts of Syria, soldiers believed to be dissidents clashed in Khan Sheikhun in Idlib province, near Turkey, but there was no report of casualties. Soldiers also searched cars for people "wanted" by the regime, the Syrian Observatory for Human Rights said.
In Damascus province, a 63-year-old man died of his wounds after being shot by security forces the previous day, the rights group added.
Meanwhile, in the coastal city of Banias, the group reported that worshippers leaving al-Radwan mosque had staged a rally calling for the "fall of the regime" and the "execution of the president".
Forces responded by raiding homes surrounding the mosque.