MIDDLETOWN (AP) — A flood of retirements has helped push Connecticut State Police overtime costs to nearly $23 million this fiscal year.

The agency is on track to finish the fiscal year that ends June 30 with an estimated $30 million in overtime costs, which has led to a $5.8 million deficit in the budget of the Department of Emergency Services and Public Protection, Hearst Connecticut Media reported Wednesday.

State lawmakers asked public safety Commissioner James Rovella last year to hold overtime costs this fiscal year to about $22 million — $4 million less than last year.

Because of increased overtime due to staffing shortages, some state police sergeants have nearly tripled their base salaries by working overtime, according to the state comptroller's website. Four sergeants earned more than $300,000 apiece last year.

State police have about 922 troopers. Since January, 30 troopers have notified officials they plan to retire, and 164 troopers will be eligible for retirement by the end of the fiscal year.

Rovella told legislators last year that trooper staffing levels could plummet 55 percent by 2023 because of retirements, if hiring isn't accelerated.

Rovella has said there are plans for two new state police academy classes that would each graduate 85 new troopers.