Amnesty International is accusing the U.S.-led coalition of potentially committing war crimes against civilians as it fought to wrest control of the Iraqi city of Mosul from Islamic State fighters. It says ISIS definitely committed war crimes there.The forces aligned with Iraq's government allegedly used crude, imprecise weapons that caused an unnecessary level of civilian casualties, the U.K.-based rights group says."The scale and gravity of the loss of civilian lives during the military operation to retake Mosul must immediately be publicly acknowledged at the highest levels of government in Iraq and states that are part of the US-led coalition," Lynn Maalouf, Director of Research for the Middle East at Amnesty International, said in a statement.The report says the number of civilians killed by attacks launched by Iraqi and coalition forces in Mosul from Feb. 19 to June 19 is at least 3,706, citing numbers from the Airwars monitoring group. IS has summarily killed "hundreds, if not thousands" of people trying to flee, Amnesty says.This week, Iraq's Prime Minister Haidar al-Abadi declared victory in Mosul, which has been under ISIS control since the summer of 2014. The offensive to take back the city began last October, and west Mosul was the last remaining ISIS stronghold there.As ISIS fighters lost territory, they would force civilians to act as human shields in the dwindling areas that they still controlled, resulting in a densely packed area, the report says."Did they [pro-government forces] try to hit IS targets? IS was with you, in your house," says an outraged west Mosul resident quoted by Amnesty.In the fight for east Mosul, elite Iraqi Counter-Terrorism Service troops fought on the ground with limited coalition airstrikes that primarily used precision-guided munitions, according to Amnesty. Casualties were high among the Iraqi troops, with some estimates of up to 75 percent of the force killed or injured.Tactics changed in west Mosul, which Amnesty attributes to fewer highly trained Iraqi forces available to fight. The rights group criticizes the choice of weapons used in west Mosul, including Improvised Rocket Assisted Munitions (IRAMs) – described by Amnesty as "inherently indiscriminate.""With their crude targeting abilities, these weapons wreaked havoc in densely populated west Mosul, where large groups of civilians were trapped in homes or makeshift shelters," the report states. "Even in attacks that seem to have struck their intended military target, the use of unsuitable weapons or failure to take other necessary precautions resulted in needless loss of civilian lives and in some cases constituted disproportionate attacks."Speaking from Baghdad, U.S. Air Force Brig. Gen. Andrew Croft responded to the report's accusations in an interview with NPR's Morning Edition. He said the coalition has "done, in my view, the absolute best job we can to avoid civilian casualties." Here's more: