Cleveland - The city of Cleveland prepared to file a claim for $500 in past-due emergency medical services expenses against the estate of 12-year-old Tamir Rice, who was fatally shot by police, according to documents provided by the city.

The claim, which is dated on Wednesday, is for Rice’s “last dying expense” and includes $450 for an ambulance and $50 for mileage, the city documents say.

The claim had not yet been officially filed with Cuyahoga County probate court, court officials said on Thursday, but media reports said the bill has been sent to Rice’s family.

“The callousness, insensitivity and poor judgment required for the city to send a bill - its own police officers having slain 12-year-old Tamir - is breathtaking,” an attorney for Rice’s mother, Samaria Rice, said in a statement to Cleveland’s CBS affiliate. “This adds insult to homicide.”

The killing of Rice, who was playing with a replica gun that shoots plastic pellets when he was shot, helped fuel the national debate over police use of deadly force, especially against minorities.

After the Rice killing, a U.S. Justice Department investigation found widespread excessive use of force by Cleveland police.

In November 2014, Rice, who was black, was shot by police officer Timothy Loehmann, who was responding to a report of a person with a gun in a park. Rice died the next day.

A grand jury in December declined to bring criminal charges against white officers Loehmann and Frank Garmback.