The regime of Syrian President Bashar al-Assad is in the midst of an unprecedented bombing campaign in Syria's largest city of Aleppo.

For the last four months, Syrian military helicopters have been dropping steel barrels packed with explosives and shrapnel out of the back of helicopters in rebel-held areas of the city.

This injured girl, in shock and covered with blood after a barrel bombing, exemplifies the reality of Assad's strategy for retaking one of the oldest cities in the world with indiscriminate force.

Here's what barrel bombings — and double barrel bombings — have looked like in various parts of Syria:

The result is sheer destruction.

A general view shows a building damaged by what activists said were barrel bombs dropped by forces loyal to Syria's President Bashar al-Assad, in the al-Myassar neighbourhood of Aleppo April 3, 2014. REUTERS/Hamid Khatib

The nails and other shrapnel in the barrels pierce the city and mangle its people.

There are a myriad of horrifying photos. The little girl, along with the distraught man in the background, depict the brutality of the crude devices while sparing the gore.

A woman comforts an injured girl at a clinic, who was injured by what activists said were barrel bombs dropped by forces loyal to Syria's President Bashar al-Assad, in Aleppo's al-Sakhour district April 2, 2014. REUTERS/Hosam Katan

More than 7 million Syrians have fled their homes and/or their country during three years of war — one million now live Lebanon — but many of the country's 23 million residents have no choice but to attempt a live in their increasingly battered neighborhoods.

Men drive a car near a site hit by what activists said was an air strike by government forces in Aleppo's al-Ansari al-Sharqi neighbourhood April 2, 2014. REUTERS/Ammar Abdullah

And as Assad — who is preparing for re-election — continues to pummel the residents of his country with Russian weapons and Iranian direction, the leaders of the free world do nothing except talk.