• Terrorist group claims it killed 48 Syrian troops in Iraq - The Guardian (blog)

Welcome to Middle East Live.

Here's a roundup of the latest developments:

Syria

• An al-Qaida group has claimed responsibility for last week's killing of 48 Syrian soldiers and nine Iraqi guards in western Iraq, AP reports. The US-based Site Intelligence Group, which monitors militant forums, says al-Qaida's franchise in Iraq issued a statement on militant websites Monday claiming the attack.

• Another 20 bodies of young men, believed to have been shot by the security forces, have been found in the "river of martyrs" in Aleppo, as the Guardian publishes an investigation by Martin Chulov into the killing of 100 people found in the waterway in January.

The Guardian interviewed 11 family members of massacre victims in the Bustan al-Qasr area, who all confirmed that their dead relatives had vanished in regime areas, or had been trying to reach them. Two other men who had been arrested at regime checkpoints and later freed were also interviewed. Both alleged that mass killings had taken place in the security prisons in which they had been held. They identified the prisons as Air Force intelligence and Military Security — two of the most infamous state security facilities in Syria.

A photo log of all of the victims of the massacre has been put on display to help families who are seeking missing relatives. Photograph: Ben Solomon for the Guardian

• European Union foreign ministers are meeting in Brussels in the latest bid to find a political solution to ending the violence in Syria. EU foreign policy chief Catherine Ashton, on her way into the meeting on Monday in Brussels, backed a political solution. "We need to stop the killing," she said.

• Syrian rebels broke through government lines to ease a siege of their positions in the central city of Homs on Sunday despite coming under fierce aerial bombardment, opposition campaigners told Reuters. Sunni rebels punched their way through government lines in the north and west to loosen a months-long army siege on their strongholds in the centre of the Syria's third biggest city. Insurgents based in the provinces of Hama and Idlib advanced on Homs this weekend from the north while brigades from rural Homs attacked government positions in its Baba Amro district.

• The UN has confirmed that 21 of it peacekeepers, captured by Syrian rebels on 6 March have been freed. The Filipino peacekeepers were held for three days in a southern village, but crossed safely into neighbouring Jordan after a brief truce was negotiated. 

• Video evidence has emerged linking the Yarmouk Martyrs Brigade, the group thought to be responsible for kidnapping the peacekeepers, an execution of a group of Syrian soldiers, and an initiative to supply rebels with Croatian weapons thought to be covertly backed by the US, according to EA World View.

This [video] places the Yarmouk Martyrs Brigade, the Dawn of Islam Brigade, the Croatian weapons, and Abu Jamal at the site of the killing of the POWs on the day of the incident the incident occurred.

• The number of refugees from the Syrian conflict, which topped 1 million last week, could triple by the end of the year if it continues at the current rate, according to the UN's refugee chief. "If this escalation goes on, we will have – and nothing happens to solve the problem – we might have in the end of the year a much larger number of refugees, two or three times the present level," the UN high commissioner for refugees, António Guterres, told reporters in Ankara.

• Western training of Syrian rebels is under way in Jordan in an effort to strengthen secular elements in the opposition as a bulwark against Islamic extremism, and to begin building security forces to maintain order in the event of Bashar al-Assad's fall. Jordanian security sources say the training effort is led by the US, but involves British and French instructors. 

Egypt

• Police officers in more than a third of Egyptian provinces have gone on strike, including in parts of Cairo and in Port Said, the troubled northern city where more than 50 people have died in the past month in clashes between police and protesters. They demand better weapons. But conversely, they also claim President Mohamed Morsi's regime is using them as unwilling pawns in the suppression of protesters who demand the regime's downfall

Iraq

• Torture and execution are pervasive in Iraq, 10 years after the US-led invasion, according to a report by Amnesty International previewed by the Independent. The report says: "thousands of Iraqis are detained without trial or are serving prison sentences imposed after unfair trials, torture remains rife and continues to be committed with impunity, and the new Iraq is one of the world's leading executioners."