Protesters have confronted visiting Arab League monitors in the Syrian city of Homs, demanding international protection.
The observers are assessing compliance with an Arab League plan to end the government's violent crackdown.
Tens of thousands of people protested in Homs as the monitors arrived, with Syrian police using tear gas to disperse some 70,000 people who took to the streets of the city.
"More than 70,000 demonstrators tried to enter Al-Saa square in the centre of the city of Homs, then security agents used tear gas to disperse them," said the Britain-based Syrian Observatory for Human Rights.
At the same time, some demonstrators were fired on with live ammunition as they made their way to the square, and four were wounded, one seriously.
The observatory said separate demonstrations were held elsewhere in the city, aimed at "exposing the ill practices and crimes of the regime”.
Before joining the march on Al-Saa square, tens of thousands staged a sit-in in the Al-Khalidiyeh neighbourhood, according to the observatory, which also reported demonstrations in the districts of Bab Dreib and Jub al-Jandali.
The protests come as Arab League observers visited the flashpoint central city to monitor a deal to end a nine-month crackdown on anti-regime protests.
Following the reported killings of 34 civilians in Homs' Baba Amro district on Monday, residents held a funeral in nearby Kefer Ayia for some of those who died, and were fired on by security services, the Observatory said.
Activists said the military pulled its tanks back from one district ahead of the Arab team's arrival, only to hide them inside government zones from which they could be redeployed within minutes.
Meanwhile, SANA state news agency reported that saboteurs blew up a gas pipeline in Homs province, where Syria's regime has been trying for months to crush dissent and mutinous soldiers.
Protesters appeared to have been emboldened by the presence of the observers, headed by veteran Sudanese military intelligence General Mohammed Ahmed Mustafa al-Dabi.
"Till now, they have been very cooperative," Mr Dabi told AFP, speaking of the authorities by telephone before holding talks with governor Ghassan Abdel Al.
A video posted by the Observatory on YouTube showed residents of Baba Amro pleading with Mr Dabi to go in and see the devastation.
"The delegation of observers entered Baba Amro, accompanied by people from the government, but did not meet the residents," Observatory chief Rami Abdel Rahman told AFP.
Syria's Dunia television said the observers also visited the Bab Sebaa district, where they "assessed the damage carried out by terrorist groups."
"They also met with relatives of martyrs and a person who had been abducted" by these groups, said Dunia, which is close to the regime, adding that many people decried the "conspiracy against Syria" to the monitors.
Western governments and human rights watchdogs blame President Bashar Al-Assad's regime for the bloodshed.
The observers are also due to travel to the protest hubs of Hama, near Homs, and Idlib in the northwest, close to the border with Turkey, the television added, without saying when.
Ahead of the observers' arrival, the army pulled back heavy armour from Baba Amro, scene of much of the violence, the observatory said, calling the move a "trick”.
