The Maricopa County Sheriff's Office misused at least $50 million from a fund for jail operations, and county supervisors may have to use the general fund to repay the money, top county officials say.

Findings by the county's Office of Management and Budget show the Sheriff's Office tapped the money to pay for functions not allowed under jail-fund rules, such as salaries for deputies who worked on public-corruption investigations into county supervisors and judges.

The findings will be presented publicly for the first time at 10 a.m. today to the Board of Supervisors.

"A very substantial amount of money is going to have to be paid back to the jail fund," County Manager David Smith told The Republic. "It's just a monumental financial headache that (Sheriff Joe Arpaio) has created."

The county would not release detailed findings Tuesday, saying the material was protected by executive-session rules, but officials provided The Republic with the key finding: $50 million in misspent detention funds.

They said the county's report will cover problems dating back about four years and involving travel, use of county credit cards and extradition trips.

Separate investigations by The Republic have documented the questionable use of public funds by high-ranking sheriff's officials, who routinely used county-issued credit cards to charge expensive meals and stays at luxury hotels.

The Republic also found that another fund meant to improve conditions in county jails was spent by sheriff's officials on out-of-state training, stays at luxury hotels, a staff party at a local amusement park and a $456,000 bus to transport inmates to court. That bus remains parked in a county lot because supervisors have refused to license and insure it, claiming it was illegally purchased.

Top sheriff's officials met with county budget officials Tuesday afternoon on the matter. Lt. Brian Lee, a Sheriff's Office spokesman, said the office "will continue to meet with them and work with them to try and resolve the discrepancies."