Upended buses barricade a street in Aleppo. The vehicles serve as protection against snipers loyal to Syria's President Bashar al-Assad, in the rebel-controlled Bustan al-Qasr neighbourhood.

Civilians in the city of Aleppo, Syria turned three buses upright as a barricade to protect themselves from snipers, giving a fragile sense of security to a city divided between forces loyal to the government and rebels.

An estimated 220,000 people have been killed in the civil war in Syria. The conflict has also prompted millions of Syrians to flee to neighbouring countries of Lebanon, Jordan and Turkey.

The country has been ravaged by civil war, with the opposition and Syrian army battling for total control.

The conflict began as an anti-government uprising, with protesters taking to the streets on March 15, 2011, inspired by similar revolts in Egypt and Tunisia. But a fierce government crackdown on the demonstrations prompted a militarisation of the uprising and its descent into today's brutal conflict.

A sheet provides cover from snipers on a damaged road in Sheikh Maksoud, Aleppo.

A boy fixes covers that were put up to provide protection from snipers in Aleppo's Aqyoul neighbourhood.

Free Syrian Army fighters take cover behind sandbags in Aleppo's Karm al-Jabal district.

Material is hung to provide cover in the besieged town of Arbeen.

Curtains are draped as protection from snipers in Aleppo's Salaheddine neighbourhood.

Children walk in front of barrels and sandbags stacked up in a makeshift cover iin the East Al-Ansari neighbourhood.

A woman walks past a makeshift barrier built using damaged buses in Aleppo.

A street vendor pushes a cart loaded with vegetables in front of pipes erected to provide protection from snipers in the old city of Aleppo.

Men ride a motorcycle in front of a cloth placed to cover the street from snipers in Saif al-Dawla district of Aleppo.

Civilians walk near upright buses barricading a street in Aleppo's rebel-controlled Bustan al-Qasr neighbourhood.