Syria defies Arab League deadline on observers
An Arab League deadline for Syria to allow an observer mission or face sanctions has passed with no response from Damascus to the ultimatum.
The deadline was set for 11:00 GMT. Earlier, the league warned it would meet on Saturday to discuss sanctions.
The league wants 500 observers to enter Syria to monitor the situation amid continuing protests, but Damascus has reportedly agreed to let in only 40.
Meanwhile, new evidence has emerged of protests turning into armed insurgency.
The BBC's Paul Wood, who travelled without permission to Syria's flashpoint city of Homs, reports that he saw a small but steady stream of defectors from the official security forces.
At least 11 people have been killed in the latest violence on Friday, say activists.
The Syrian Observatory for Human Rights, based in the UK, says the deaths occurred in Homs, Damascus, Deir el-Zour and in the southern province of Deraa.
Other activists - from the Local Co-ordination Committees based in Syria - say as many as 26 people have been killed.
A United Nations human rights panel has expressed alarm at reports it received of security forces in Syria torturing children.
The Geneva-based UN Committee against Torture says it has received "numerous, consistent and substantiated reports" of widespread abuse in the country.
"Of particular concern are reports referring to children who have suffered torture and mutilation while detained," said the panel's chairman, Claudio Grossman.
He also cited reports of "extrajudicial, summary or arbitrary executions; arbitrary detention by police forces and the military; and enforced and involuntary disappearances".
The committee said the Syrian authorities had been acting with total impunity while committing what it called "gross and pervasive" human rights violations.
The panel normally reviews each country's record every four years, but took the unusual step Friday of issuing a spontaneous demand to the Syrian government to explain its actions.
More than 3,500 people have died since protests against the Syrian government began in March, the UN estimates.
The government of President Bashar al-Assad blames the violence on armed gangs and militants.
Syrian state television has also blamed militants for an attack on Thursday in which it said six elite military pilots were killed.
"An armed terrorist group undertook an evil assassination plot that martyred six pilots, a technical officer and three other personnel on an air force base between Homs and Palmyra," a military spokesman was quoted as saying.
Reports on Thursday suggested that military defectors from the Free Syrian Army (FSA) had said they carried out the attack, but an FSA spokesman later denied responsibility in a BBC interview.
The spokesman, Maher Al-Rahmoun al-Naaimi, said the claim had actually been posted on a fake Facebook page set up in the group's name by Syrian intelligence.
Reports from Syria are difficult to verify as foreign journalists are unable to move around the country freely.
The Arab League set the deadline for Syria to sign the observer deal - which is a part of a broader peace plan - at a meeting in Cairo on Thursday.
An unnamed Arab source told Reuters news agency that Mr Assad's government would be given until the end of the day to answer.
Earlier this month, the league voted to suspend Syria and warned of unspecified sanctions for not implementing the peace plan.
One of the main sticking points was Damascus' demand to amend the proposal for the 500 observers to be allowed in to Syria.
The Syrian government reportedly wanted to reduce the number to 40 - a request rejected by the 22-member league.
An earlier deadline for Syria to end its crackdown passed last Saturday night with no sign of the violence abating.
The options for sanctions include a suspension of commercial flights to Syria and a halt to all dealings with its central bank.
Damascus depends on its Arab neighbours for half of its exports and a quarter of its imports, according to news agency AFP.
In Cairo, diplomats also appealed to the UN to prevent further violence, asking the world body "to take all measures to support the efforts of the Arab League to resolve the critical situation in Syria".
On Friday, Turkish Foreign Minister Ahmet Davutoglu described the league's deadline as the "last chance" for the Syrian government.
However, Russia again voiced its opposition to the outside pressure, calling for talks between Damascus and the opposition.
France earlier suggested that some sort of humanitarian protection zones be created inside Syria, the BBC's Jon Leyne in Cairo reports.
It is the first hint that international military intervention is under consideration, our correspondent adds.
'Stream of defectors'
Meanwhile, the BBC's correspondent Paul Wood and cameraman Fred Scott have obtained first-hand evidence that the struggle for democracy in Syria is becoming an armed insurgency.
The BBC saw supporters of the opposition Free Syria Army group bringing in guns from Lebanon on old smuggling routes.
Our correspondent says he witnessed casualties coming out the same way in the area which is mined and full of Syrian patrols, but not completely sealed.
Once inside Syria, he saw a steady stream of defectors and exchanges of fire when their former comrades tried to stop them, our correspondent says.
A group of five defectors told the BBC that they had decided to change sides after being ordered to fire on pro-democracy protesters in Homs.
Almost from the beginning, it has been the Syrian government's stance that armed groups are supporting the opposition.
Now that myth of an armed insurgency is becoming reality, our correspondent adds.
Earlier, the head of the FSA, Riyad al-Asad, told the BBC that President Assad was now "finished".
Speaking from a refugee camp in Turkey, he said: "Even if the outside world doesn't help us or stand with us, the Syrian nation is determined to bring down this dictator."
"The system is rotten to the core. It looks strong, perhaps, on the outside but it is weak at the heart," the former colonel in the air force added.
The FSA was formed in August 2011 by army deserters.