The Syrian government used controlled explosives and bulldozers to destroy thousands of residential buildings, a leading human rights group has claimed.
Human Rights Watch released a series of images as part of a 38-page report which appear to show the demolished areas before and after the demolition.
The report claims seven districts in and around the capital Damascus and the central city of Hamas were flattened between July 2012 and July 2013 in order to punish civilians sympathetic to the opposition.
The charity, who based their report on the images and interviews with witnesses, alleges that many of the demolished buildings were apartment blocks and that thousands of families have lost their homes as a result of the destruction.
They claim that government officials and local media have said the demolitions are part of urban planning or an effort to remove illegally constructed properties.
President Assad's forces reportedly supervised the demolitions.
A leading researcher for Human Rights Watch said the alleged demolitions were the latest additions to a "long list of crimes committed by the Syrian government":
"Wiping entire neighbourhoods off the map is not a legitimate tactic of war. These unlawful demolitions are the latest additions to a long list of crimes committed by the Syrian government," Ole Solvang, emergencies researcher for HRW, said.