The city of Cleveland wants the family of Tamir Rice, the 12-year-old boy killed by police, to pay hundreds of dollars to the government to cover “emergency medical services” for the child’s “last dying expense”, according to records.

The city’s attorneys filed a claim on Wednesday against Rice’s estate alleging that the family owes $500 for an unpaid EMS bill from the boy’s death, sparking outrage from Ohio supporters of the family who described it as a particularly cruel legal maneuver.

“The callousness, insensitivity, and poor judgment required for the city to send a bill after its own police officers killed a 12-year-old child is breathtaking,” Subodh Chandra, the family’s attorney, said in an email. “This adds insult to homicide.”

Cleveland police officer Timothy Loehmann fatally shot Rice, who was black, on 22 November 2014 – within two seconds of arriving at a local park, in response to a 911 caller who warned of a juvenile carrying a weapon that was “probably fake”.

Loehmann later testified that he thought Rice, who had a toy gun on him, was 18 years old.

News of the $500 claim comes two months after a grand jury declined to indict Loehmann, which means the officer will not face criminal charges.

According to documents sent to the estate with the claim, the $500 covers $450 for ambulance services and $10 for “mileage”.

Loehmann and another officer did not check Rice’s vital signs or perform first aid in the minutes after he was shot, but did physically restrain the boy’s sister when she attempted to reach him.

The request for money from the family comes from a city that earned widespread scorn after it claimed in a defense document last year that the 12-year-old’s own actions “directly and proximately” caused his death.

The family has called on the US department of justice to investigate the shooting.

Cleveland city officials did not immediately respond to requests for comment Wednesday night.