LOS ANGELES - MICHAEL Jackson's family on Thursday announced a free memorial service for the late pop icon on Tuesday at the Staples Center arena in Los Angeles.

Some 11,000 tickets will be distributed free of charge for the event, a public relations firm representing the family said in a statement. It said the memorial service would take place at 10am (1700 GMT, 12am Singapore time) on Tuesday.

Randy Phillips, chief executive of concert promoter AEG Live, told reporters on earlier Thursday Jackson's much-anticipated memorial was being planned for the rock concert and sporting venue, the Staples Center, in downtown Los Angeles.

AEG Live is part of a group of companies that controls events at the Staples Center. Mr Phillips said details of the memorial in the 20,000-seat indoor arena were still being discussed but fans would not be charged for tickets.

Jackson's death on June 25 after suffering cardiac arrest at his rented Los Angeles mansion has provoked worldwide tributes from fans and musicians and sent many of his records back into the top of music charts.

The Staples Center is the site of the singer's last rehearsals for a planned 50-concert comeback tour in London that was due to start on July 13 and was backed by AEG Live.

Video clips of a rehearsal two nights before he died, that showed Jackson looking thin but performing more like his old superstar self, were released to CNN on Thursday.

An official autopsy has been performed but toxicology tests won't be ready for weeks. Results of a private autopsy by a Jackson family doctor have not been released.

Law enforcement sources said the US Drug Enforcement Administration had been asked to help Los Angeles police in their investigation. Several bags of medicines have already been removed from Jackson's house by coroner's officials.

Speculation has swirled in the media that the 50-year-old pop star was abusing prescription drugs and perhaps intravenous drugs before comeback concerts this month in London.

His brother Jermaine Jackson said on Thursday that reports of Michael Jackson's possible drug use had hurt his family.

'Michael has always been a person who was against anything like that. ... But in this business the pressures and things that you go through, you never know what one turn(s) to,' Jermaine said on NBC's 'Today' show. -- REUTERS