Satellite images have laid bare the suffering inflicted on Syria’s largest city, a London-based rights group said Wednesday, cataloguing hundreds of damaged or destroyed houses and more than 1,000 roadblocks.

Amnesty International said it had worked with the American Association for the Advancement of Science to analyze pictures of Aleppo taken by aerospace imagery providers DigitalGlobe and Astrium for signs of destruction in the metropolis, which has been the scene of months of vicious fighting between forces loyal to Syrian President Bashar Assad and the rebels fighting to topple him.

“Satellite images really speak for themselves,” said Donatella Rovera, a senior Amnesty adviser who recently returned from a trip to Aleppo. “You can see really clearly buildings - groups of buildings - that were there a year ago that are no longer there today, and we’re matching those with research on the ground so we know exactly the areas that were struck, when, by what kind of weapons.”

The siege of Aleppo has its roots in the largely peaceful protests against Assad’s rule which broke out in early 2011. The regime responded with brutal force, and the protests morphed into an armed uprising and a civil war. The rebels launched an ambitious attempt to capture Aleppo last year, but they have been unable to solidify their hold on the commercial hub, which has since become the object of a bloody tug of war.

Many of the photographs released by Amnesty show a general view of the city, with red dots meant to indicate damage and destruction. The rights group said in a statement that the damage was “emblematic of the relentless bombardment.”

Rovera said analysis of high-resolution pictures showed more than a thousand roadblocks and hundreds of housing units affected by the damage. She said more precise estimates weren’t possible, in part due to the difficulty of picking out fire or structural damage from space. But she said it was clear from the photographs that rebel-held areas were far worse affected than government-held neighborhoods.

“That has been a pattern not just in Aleppo but throughout Syria,” she said. “Wherever a village or a part of town comes under control of opposition forces it then gets pounded mercilessly by government forces.”

The damage was obvious in close-up images which Amnesty said showed the aftermath of the Assad government’s ballistic missile strikes. “Before” photographs from Aleppo neighborhoods of Ard al-Hamra, Tariq al-Bab, and Jabal Badro showed tightly-packed houses casting late afternoon shadows over streets and parkland. “After” photographs showed block-wide patches of destruction where the rights group said missiles had slammed into residential areas.

From space, the bright white of the rubble against the dark outlines of the houses looked like small mounds of crushed chalk on an open newspaper. Up close, Amnesty said the devastation had been catastrophic.

In Jabal Badro, a missile killed scores of people when it hit on the evening of Feb. 18, the rights group said. In Ard al-Hamra and Tariq al-Bab, it said twin missile strikes on Feb. 22 left at least 117 residents dead.

Another set of images, from March and May of this year, showed what the rights group said was part of the widespread damage within the Old City of Aleppo, home to a massive medieval citadel, and various venerable religious schools, palaces, baths, and trading posts.

The one taken in March showed the famous leaning minaret of Aleppo’s Great Mosque casting a long shadow over an adjoining plaza.

In the image from May the shadow was gone; the 11th-century architectural treasure had been obliterated.