CNN)ISIS executed 284 men and boys as coalition forces closed in on Mosul, an Iraqi intelligence source told CNN.

Those killed on Thursday and Friday had been rounded up near and in the city for use as human shields against attacks that are forcing ISIS out of the southern sections of Mosul, the source explained.
ISIS used a bulldozer to dump the corpses in a mass grave at the scene of the executions -- Mosul's defunct College of Agriculture in the north of the city, the intelligence source said.
The victims were all shot and some were children, said the source, who wanted anonymity because he is not authorized to speak to the media. CNN could not independently confirm the claim