While waiting for toxicology reports to come back giving cause to the death of Amy Winehouse, detectives are reviewing security camera surveillance footage along with a drug dealer's testimony for answers.

According to the Daily Mirror, surveillance footage is being analyzed to see if Amy Winehouse went out the Friday night before she died after her drug dealer reportedly stepped forward with clues.

"There are enough cameras in the area to get a picture of her movements," a source said in a statement to the Daily Mirror. "It's a painstaking operation which involves going through tens of hours of footage."

Tony Azzopardi, a 53-year-old London drug dealer, said he sold Winehouse £1,200 (about US$2,000) worth of crack cocaine and heroin hours before she died. He was questioned by police on Monday, where he was attacked by a flock of reports leaving the station, as reported by Fox News.

"I want Amy's family to know the truth about what happened," Azzopardi told the Mirror. "I want to help them out -- but I'm worried about my safety."

Azzopardi was expected to be questioned again on Tuesday according to the Mirror.

Amy Winehouse was found dead in bed in her London flat on July 23. Her last conversation is believed to have been with her security guard the night before.

An autopsy for Amy Winehouse done on July 25 came back inconclusive. A toxicology report is due within two to three weeks which can explain the cause of the death of Amy Winehouse.

Police officials say there was no report of drugs or drug paraphernalia in Winehouse's flat.

According to friends of the belated singer, Winehouse was engaging in "wild drinking" and drug use the night before she died.

Mitch Winehouse, Amy's father, claims she was drug-free for three years before her death.

"Three years ago, Amy conquered her drug dependency," Mitch Winehouse said in the eulogy, which was excerpted in the Daily Mail. "The doctors said it was impossible but she really did it.  She was trying hard to deal with her drinking and had just completed 3 weeks of abstinence.

"She said, 'Dad I've had enough, I can't stand the look on your and the family's faces anymore.'"