Secret police raided homes near Damascus overnight, rights campaigners said , as popular opposition to President Bashar al-Assad mounted following the bloodiest attacks on pro-democracy protesters in weeks of demonstrations.
Security operatives in plain clothes wielding assault rifles broke into homes in the suburb of Harasta just after midnight on Sunday, arresting activists in the area, known as the Ghouta, or the old garden district of the capital.
The London-based Syrian Observatory for Human Rights said on Sunday that security forces had arrested dozens of people in raids across the country. It gave the names of 18 men who were arrested in the northern cities of Idlib, Raqqa and Aleppo.
On Sunday, Human Rights Watch, the New York-based rights watchdog, called on the US and European Union to impose sanctions on Syrian officials responsible for the killing, arbitrary detention and torture of pro-democracy protesters.
"After Friday’s carnage, it is no longer enough to condemn the violence," said Joe Stork, HRW's deputy Middle East director. "Faced with the Syrian authorities' 'shoot to kill' strategy, the international community needs to impose sanctions on those ordering the shooting of protesters."
Al Jazeera's Rula Amin in Damascus reported that pro-democracy activists in Nawaa, near Daraa, have called on people to take part in funerals that are to take place there for six people who have been killed in the recent violence.
Security forces and gunmen loyal to Assad killed at least 112 people in the last two days when they fired at protests demanding political freedoms and an end to corruption on Friday and on mass funerals for victims a day later.
On Sunday, the Syrian state news agency named 38 policemen that it said had been injured by "armed groups" on Saturday. It said that the total number of security forces injured since unrest began is 286.
It also reported that five security personnel had been killed in Nawaa, near Deraa, when they were attacked by "gunmen". It said five others were wounded in the clash, in which two "members of the armed group" were killed and 15 others injured.
Two Syrian legislators resigned their posts in parliament as outrage grows over the security forces' ongoing crackdown on anti-government protests.
Nasser al-Hariri and Khalil al-Rifaei, independent MPs who represent the city of Daraa, where scores of protesters have been killed, both separately told Al Jazeera on Saturday that they were resigning over the killings of demonstrators.
"I feel sorry for those who were killed in Houran today and yesterday by the bullets of security forces, despite the fact that the president has promised no live ammunition by security forces at all," al-Hariri said.
He was referring to the deaths of protesters a day earlier, as well as the deaths of mourners killed on Saturday when security forces opened fire at a funeral procession.
"Being an MP I feel the need to step down, as long as I am unable to protect the voters killed by live ammunition and so I feel better to resign," he said.
Al-Rifaei said: "I convey my condolence to the people of Houran and the Syrian people. The Syrian people and the people of Houran voted for me to be a member of parliament and now I can't protect them anymore."
Rezq Abdulrahman Abazeid, the government-appointed mufti for Daraa, which has been a focal point for pro-democracy protests, also resigned on Saturday in protest at the killing of demonstrators by security forces.
At least 15 people were reported killed on Saturday and more than 220 protesters have been killed since protests against the government of Bashar al-Assad, the Syrian president, erupted on March 18 in Daraa, rights campaigners say.
|Map of April 22 'Great Friday' protests across Syria
At least four people were killed in the Damascus suburb of Douma, a witness told Al Jazeera, after security forces on the ground and snipers on rooftops opened fire on a crowd of mourners.
Eyewitness in Douma on Saturday said that the gunfire erupted during the funeral processions, a day after eight people were killed and at least 25 injured in an attack on protesters.
Snipers took up positions on the top of a Baath Party building near the privately-run Hamdan Hospital, where residents had overnight formed a human shield around the main gate, in order to prevent security forces from arresting those who were injured and being treated inside.
Elsewhere, at least three people were killed in the neighbourhood of Barza at a mass funeral of pro-democracy protesters killed a day earlier.
Al Jazeera's Amin reported that people at the funeral in Barza said that gunmen on the street were "randomly shooting at people".
Also on Saturday, Daniel Saud, the head of the rights group the Committees for the Defence of Democracy, Freedoms and Human Rights in Syria, was arrested and taken to an undisclosed location, according to Khalil Maatouk, his lawyer.
'Long live Syria'
Outside of the capital, six people are thought to have been killed as security forces opened fire on people seeking to join mass funerals in the southern village of Izraa, where witnesses said at least 12 funerals were taking place.
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Mourners there were heard chanting: "Bashar al-Assad, you traitor! Long live Syria, down with Bashar!"
A special correspondent for Al Jazeera, reporting from just outside Izraa and who cannot be named for security reasons, confirmed that he had witnessed a funeral procession being fired upon.
"[People marching on an overpass] were met with a hail of gunfire, many people certainly wounded directly in front of us, cars turned around, and I can tell you it was an incredibly chaotic scene, and it seems as though pretty much everyone down here in the southern part of the country is now carrying weapons," he said.
"It is unclear who was firing at whom, that's part of the confusion."
Syrian state television has reported that the security forces are responding to clashes between the protesters and supporters of the government.
State media says that most of the killings have been the result of these clashes.
World powers have called on Syria to end the violence, with Barack Obama, the US president, telling Syria its crackdown on protesters must stop.
"This outrageous use of violence to quell protests must come to an end now," Obama said.
Syria responded angrily to Obama's comments, saying they lacked objectivity.
The latest security crackdowns follow widespread demonstrations on Friday that have been termed the "Great Friday" protests. The day was also the bloodiest so far.
Amnesty International, the London-based human rights group, said that at least 75 people were killed in the government's crackdown on Friday.
Syrian activists sent Al Jazeera a list naming 103 people from across the country who they said had been killed by security forces on Friday.
Al-Assad appeared to make some concession to the protesters on Thursday, signing a decree that lifted Syria's emergency law, but the move is seen by the opposition as little more than symbolic, since other laws still give entrenched security forces wide powers.