MASSAPEQUA - What began as a teenage joyride ended with a car crashing into the backyard of a home, and now, Nassau Police Department's Internal Affairs Department is investigating the case. Homeowner Vincent Grande says he came home from dinner last Saturday to find several police cars at his house and a car on his lawn. Neighbors told him the car came over the curb, went through a garden, slammed into his sprinkler system and nearly hit his house. Grande estimates up to $7,000 damage was done to his property. According to a police report obtained by News 12 Long Island, a 15-year-old neighborhood boy was behind the wheel. The report says he had taken his parents' car without permission. Grande says he asked for the teen to be arrested, and received an obscene gesture in return from the boy's father.No one answered the door at the teen's home today. In a statement, police officials said, "The Nassau Police Department is aware of the incident. It is documented in a case report and that case is being investigated by the Internal Affairs Department."The Internal Affairs Department typically investigates police misconduct, but it's unclear what alleged misconduct the department is checking out.