Credit: Jordin Althaus/

Andrew Koppel, the son of former ABC News anchor Ted Koppel, died last month from a lethal dose of alcohol plus illegal and prescription drugs, the New York City medical examiner announced Friday.

The medical examiner, which lists his May 30 death as an accident, said Koppel, 40, suffered from acute intoxication due to the combined effects of alcohol, heroin, cocaine and the generic form of the painkiller Valium.

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Before his death, Koppel, an attorney for the city's Housing Authority who lived in Queens with his girlfriend and baby daughter, had been drinking all day Memorial Day in New York City.

He ended up with a drinking buddy at a seedy Washington Heights apartment around 11 p.m. where he was later found unconscious and not breathing.