Actress Lindsay Lohan was dating actor Heath Ledger when he died in 2008, according to an audio tape published Thursday by Radar

Lohan's relationship with Ledger was unknown until the tape was released. It shows the actress' mother Dina speaking to her ex-husband Michael Lohan in a 2008 phone conversation about the alleged relationship.

According to the tape, Lindsay was shocked by the death of Ledger and Dina is afraid that something similar may happen to her daughter.

And she [Lindsay] was dating Heath when he died. I don't know if you know that, but I know cause I would drop her off and they were friends very, very close, ok? Dina says. That f---d her up, she continued.

Ledger also dated actress Michelle Williams for three years to whom he bore their daughter Matilda. In 2007 the couple broke up and a year later, in January 2008, the actor was found dead at his New York apartment from a drug overdose. He was 28.

Lohan's most controversial relationship is with girlfriend DJ Samantha Ronson to whom she reportedly split around April this year.