Syrian armoured vehicles have entered the northern coastal city of Latakia, witnesses say, a day after at least 17 people were reported killed in nationwide protests against the government of President Bashar al-Assad.
Witnesses and activists said two people had been killed in Latakia's al-Ramel district on Saturday after tanks rolled into the city amid intense gunfire.
The UK-based Syrian Observatory for Human Rights said around 20 tanks and armoured personnel carriers had been deployed.
"Heavy gunfire could be heard from 10:30am until midday [07:30 to 09:00 GMT]," Rami Abdel Rahman, head of the group, said, adding that large numbers of people were fleeing the area.
A Latakia resident confirmed the military's presence in al-Ramel to Al Jazeera, speaking on the condition of anonymity for fear of reprisals.
"There are tanks entering into Latakia, the area of south Ramel [and] heavy gunfire in all neighbourhoods. There are also heavy artillery shellings. We are not sure if it is artillery or tank shells. This has been going on since the morning in south Ramel," he said.
"The army and security personnel together with regime thugs are shelling residential neighbourhoods. There are no armed gangs here. We have been demonstrating peacefully for the last three months. However the regime claims there are armed groups among the residents here. This is not true."
Activists also said a child had been shot dead by a sniper in the eastern city of Deir ez-Zor.
'Violence must end'
The reports of violence came as US President Barack Obama spoke with the leaders of Saudi Arabia and the UK and all three called for an immediate end to the Syrian government's crackdown on protests.
Obama and Saudi King Abdullah "expressed their shared, deep concerns about the Syrian government's use of violence against its citizens," the White House said in a statement.
"They agreed that the Syrian regime's brutal campaign of violence against the Syrian people must end immediately, and to continue close consultations about the situation in the days ahead."
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Similar language was used in a statement after a separate Obama conversation with British Prime Minister David Cameron.
Tens of thousands of people rallied in cities across the country on Friday in protest against the government and at least 17 people were reported killed.
Protests took place up and down the country, including Douma, Aleppo, Homs, Hama and Deir ez-Zor.
Five people were reportedly killed in the Damascus suburb of Douma.
In Homs, north of the capital, one man was shot and killed as security forces fired on worshippers leave the Aadawiyya Mosque following prayers, a local activist told Al Jazeera.
Another man was killed in Hama near the Tawheed Mosque when security forces opened fire after prayers.
Hama has been under a military siege since the beginning of Ramadan, and local activists report at least 200 people have died there, while more than 1,000 have been arrested.
Syrian authorities have expelled most independent journalists since the five-month-old uprising against Assad began, making it difficult to verify reports from both sides.
'Assad lost legitimacy to lead'
US Secretary of State Hillary Clinton said on Friday that Syria would be better off without Assad and called on nations that buy oil or sell arms to Syria to cut those ties.
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"We urge those countries still buying Syrian oil or gas, those countries still sending Assad weapons, those countries whose political and economic support give him comfort in his brutality, to get on the right side of history," she said.
"President Assad has lost the legitimacy to lead and it is clear that Syria would be better off without him," Clinton told reporters on Friday, alongside visiting Norwegian Foreign Minister Jonas Gahr Stoere.
But Clinton stopped short of explicitly demanding that Assad step down, a call US officials say Obama's administration has decided to make in the coming days.
The US is being careful to promote a broad international response "so that there will not be any temptation on the part of anyone inside the Assad regime to claim that it's only the United States" or the West leading the campaign against Damascus, she said.
She added that the "entire world" was against the crackdown.
Clinton also said that the US ambassador to Damascus, Robert Ford, had delivered a "clear message" to the Syrian government, alluding to his meeting Thursday with Syrian Foreign Minister Walid al-Muallem.
"Immediately stop the violence, withdraw your security forces, respond to the legitimate aspirations of the Syrian people for a democratic transition in concrete and meaningful ways," she said, reading out the message.