Henoc Zaragoza-Alvarez, 26, of 133 Tresser Blvd., was charged with first-degree criminal mischief and second-degree threatening in the incident, police said.
After he was told to leave the party in the area of Elmcroft Road and Belden Street, guests heard the sound of breaking glass, which they assumed was the suspect breaking a bottle, police said.
But when the ex-girlfriend left the party, she discovered the damage to the windshield, police said.
Police were contacted, and Zaragoza-Henoc was charged later Sunday afternoon.
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