The city Comptroller’s Office is set to release a report blasting Mayor de Blasio’s administration for the soaring costs of keeping inmates at Rikers Island as violence at the prison continues to rise, it was reported Thursday.

In the report due out Friday, Comptroller Scott Stringer faults de Blasio for failing to show “any real results or improvements” even though it cost the city $112,665 per inmate to run the jails in 2015 — a 17 percent increase over the previous year, The New York Times said.

“There is definitely something wrong with this picture,” Stringer told the Times. “The jail population in New York City is the lowest in 31 years, but the rate of violent incidents is accelerating at an alarming pace.”