Amy Winehouse
Amy Winehouse's cause of death is still a mystery. Toxicology reports revealed were "no illegal substances" in her body at the time of her death, the singer's family said. . Reuters

Singer Amy Winehouse's father said that his daughter had the prescribed medication Librium in her system when she died of a seizure, caused by alcohol detoxification, said media reports Friday.

Talking at a taping of segment for journalist Anderson Cooper's new talk show Anderson, the Rehab singer's father Mitch Winehouse, 60, repeated earlier statements saying that his daughter had no illegal drugs in her system, Reuters reported.

What happened to Amy wasn't anything to do with drugs, Winehouse said.

With popular songs like Rehab and Back to Black, the 27-year-old soul singer scored many hits. However, despite she rose to stardom, Winehouse battled drug and alcohol addiction.

Winehouse was discovered dead in her £2 million home by her security guard just before 4 p.m. on July 23. At that point of time, it was widely believed that substance abuse was the root cause of her death. But, according to her toxicology report issued last month, there were no illegal drugs found in her system.

According to Mitch Winehouse, the only drug in her system was a small amount of Librium, which is used to help people overcome alcohol detoxification.

He said last month that she had conquered her drug addiction and was trying hard to deal with her drinking.

A theory is that her body couldn't cope with the quick withdrawal, said another source close to the family.