Islip Town Supervisor Pete McGowan pleaded guilty to four criminal charges Thursday, just hours after tendering his resignation.

McGowan, under investigation for months by the Suffolk district attorney, pleaded guilty to grand larceny, tampering with a witness, bribe receiving and filing a false instrument. He will also be required to pay back $1.1 million to campaign contributors. Authorities say McGowan used that money for personal expenses, including vacations, bar and restaurant tabs and a car.

Islip Town spokesperson Patricia Kaloski says McGowan sent a one-sentence letter to Town Attorney Peter Cohalan tendering his resignation as of 9 a.m. Thursday. McGowan will be sentenced May 4 and is expected to serve one to three years in prison.

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