Michael Jackson's brain is still being kept by doctors and tested for drugs that may have contributed to his death.

Pathologists are checking for neurochemical traces of painkillers and other drugs before returning the brain - or at least part of it - to the singer's family for burial.

Confusion: Dr Klein is quizzed on TV about Michael Jackson

However, no date has been given for returning it, adding to the confusion about when and where the singer will be buried, and while the tests are ongoing his cause of death at the age of 50 remains officially "deferred".

There is also a chance the Los Angeles coroner will hold on to evidential samples of brain tissue.

Ed Winter, the assistant chief coroner, said: "As soon as we are done with the brain, we will return it. The last I heard, they are not burying the body yet."

There is also no word on the current location of the superstar's body, wheeled out without its brain at the staples Centre in LA for Tuesday's public memorial in a £15,000 gold-plated casket. officials at the Forest Lawn Memorial Park in Hollywood Hills, where the family held private services, have refused to comment on whether it is being stored there and the singer's final resting place still remains a mystery a fortnight after he died at his rented home in LA.

Three of Jackson's brothers, Jermaine, Jackie and Tito, are reportedly negotiating for him to be laid to rest at his former neverland ranch north of LA. Californian officials said creating a cemetery at the rural estate near santa Barbara could take weeks. But ABC news in America claimed a family source confirmed the brothers have begun a lengthy bid to establish a state-sanctioned burial ground in the 2,800-acre grounds.

To add to the confusion, Jackson's former dermatologist has dodged questions on Good Morning America about whether he was the sperm donor father of Prince Michael, 12, and Paris, 11 - the eldest two of the star's three surrogate-born children.

Dr Arnold klein said: "To the best of my knowledge I am not the father. But if push comes to shove I cannot say anything about it."

Dr klein said Jackson considered his face "a work of art" and denied the singer wanted to change his skin colour.He added: "He was developing severe speckling and you can't look like a leopard. You have to even your skin tone."

It came as the producers of London's Thriller - Live musical announced plans for a worldwide tour. The West End Michael Jackson tribute show will begin a 12- month tour in Munich on 21 July and dates have been confirmed in most other European countries and the Us.