More than 130,000 people have been killed since the beginning of the conflict in Syria nearly three years ago, the Syrian Observatory for Human Rights said on Tuesday.

The conflict in Syria began in March 2011 as peaceful protests against four decades of rule by President Bashar al-Assad's family, but turned into an armed insurgency whose sectarian dimensions have reverberated across the Middle East.

The monitoring group, which is based in Britain and relies on a network of sources across Syria, said 130,433 people have been killed since the conflict began in March 2011, including 46,266 civilians.

They include more than 7,000 children and more than 4,600 women, the watchdog said.

Some 52,290 pro-government fighters had been killed, the Observatory said, among them more than 32,000 regular troops and 262 reinforcements from the Lebanese Shiite movement Hezbollah.

On the rebel side, the anti-Assad Observatory counted 29,083 deaths, including 6,913 fighters from jihadist groups like the Islamic State of Iraq and the Levant.

The Observatory said at least 17,000 people are being held in government prisons while more than 6,000 government supporters are in the custody of Islamist rebels.

It had also recorded the deaths of 2,794 unidentified individuals.

(Al Arabiya with Reuters and AFP)