Brian Oxman, attorney and spokesman of the late singer, told 'CNN' that there were "enablers" in the star's entourage, who pressurized the singer to perform and pushed him towards prescription drugs.

"I believe (his manager) Frank DiLeo was with him at the time (of his heart attack), that is what I have been told. This family has been trying for months and months and months to take care of Michael Jackson," said Oxman.

"The people who have surrounded him have been enabling him. If you think the case of Anna Nicole Smith was an abuse, that is nothing compared to what has taken place in the life of Michael Jackson," Oxman added hinting at the role of the coterie that surrounded Jackson during his last days.

"I do not know what medications he was taking, but the reports that we have received within the family are that they were extensive. I do not know the cause of it. But it is something that I feared. This is a case of abuse of medications, unless the cause is something else," Oxman said.

The singer, who had a history of addiction to pain killers, was reportedly on a number of prescribed drugs to combat injuries suffered during his training for the comeback.

"When you warn people that this is what's going to happen and then it happens, where there's smoke there's fire," Oxman added.

According to US magazine 'Life & Style', the singer had been popping pills, including anti-anxiety drugs Xanax and Zoloft and painkiller Demerol, for weeks before his death and that an overdose had caused respiratory and cardiac arrest.

Meanwhile British tabloid Sun quoted a Jackson aide who said, "Shortly after taking the Demerol he started to experience slow shallow breathing. His breathing gradually got slower and slower until it stopped."

Jackson, who was reportedly under huge debt, was hoping a turn of fortune with the success of his 'This Is It' concert series but had expressed his discomfort over the extended dates of the show, which was increased from 10 to 50. I went to bed knowing I sold 10 dates, and woke up to the news I was booked to do 50. I don't know how I'm going to do 50 shows. I'm really angry with them booking me up to do 50 shows. I only wanted to do 10," the star was quoted as saying by newspapers, but the reports were later denied by show organisers AEG Live.

The company had sold tickets worth 85 million for the 50-date concert tour that was to be held in London's famed O2 Arena from July 13.

The Los Angeles based company had already invested USD 20 million in the comeback concert tour which was to be the 50-year-old star's "final curtain call".

It had invested millions to mount a production that was to include up to 22 sets, elaborate light shows and high-wire acts.

AEG will now have to refund the amount to approximately 750,000 people across the globe.