Reuters has the latest details on the bombing raid in Aleppo, Syria conducted by President Bashar al-Assad’s forces over the weekend:

Seventy-six people, including 28 children, were killed on Sunday when Syrian army helicopters dropped “barrel bombs” on the northern city of Aleppo, the Syrian Observatory for Human Rights said on Monday.

Barrel bombs are explosive-filled cylinders or oil barrels, often rolled out of the back of helicopters with little attempt at striking a particular target but capable of causing widespread casualties and significant damage.

Here’s a map of the districts of the city that were hit:

Here’s more on the state of the 2 1/2-year-old conflict:

They have been unable to recapture eastern and central parts of Aleppo, which rebels stormed in the summer of 2012, but they have driven rebel fighters back from towns to the southeast of the city in recent weeks.

The conflict has grown sectarian, with majority Sunni rebels battling Assad’s own Alawite sect and Shi’ite militia.