Michael Jackson's grieving family has released a statement describing the King of Pop’s passing as one of “our darkest moments”.

In the letter, released on the celebrity magazine website People.com, Jackson family patriarch Joseph told of the family’s despair at his sudden death from a heart attack last Thursday.

“In one of the darkest moments of our lives we find it hard to find the words appropriate to this sudden tragedy we all had to encounter,” Mr Jackson said.

“Our beloved son, brother and father of three children has gone so unexpectedly, in such a tragic way and much too soon. It leaves us, his family, speechless and devastated to a point, where communication with the outside world seems almost impossible at times.

“We miss Michael endlessly, our pain cannot be described in words. But Michael would not want us to give up now. So we want to thank all of his faithful supporters and loyal fans worldwide, you – who Michael loved so much. Please do not despair, because Michael will continue to live on in each and every one of you. Continue to spread his message, because that is what he would want you to do. Carry on, so his legacy will live forever.”

Mr Jackson also added that the singer’s three children – Michael Joseph, 12, known as Prince, Paris Michael Katherine, 11, and their seven-year-old brother Prince Michael II, known as Blanket - were also touched by the support flooding in from fans worldwide.

"My grandchildren are deeply moved by all the love and support you have shown for them and their father, Michael Jackson," Mr Jackson said on behalf of the family.

The statement was released on Saturday as the family sought a second, independent, autopsy and police were set to question the personal doctor who was with Jackson when he died.

Jackson's personal physician, Texas cardiologist Dr Conrad Murray, was with the singer when he collapsed at his rented mansion on Thursday. Dr Murray hired an attorney to accompany him to what was expected to be a lengthy meeting with the Los Angeles Police Department on Saturday evening.

"Dr Murray is considered to be a witness to the events surrounding Michael Jackson's death and he is not a suspect," Houston law firm Stradley, Chernoff & Alford said in a statement.

"Dr Murray hired legal counsel to help guide him through the police investigation process. The law firm was hired to make sure the police investigation is conducted properly."

An LAPD spokeswoman said she had no updates on the meeting, three hours after it was scheduled to begin.

According to media reports, Jackson was injected with the narcotic painkiller Demerol shortly before he went into cardiac arrest. Dr Murray was desperately trying to revive Jackson when paramedics arrived, and he rode with the singer in an ambulance to the hospital where the pop star was pronounced dead.

The official autopsy, conducted on Friday, failed to determine what killed Jackson, pending toxicology tests that were expected to take up to six weeks. Such tests could reveal the presence of drugs in his system.

Over the weekend hundreds of fans continued to gather outside the Jackson family compound in Encino, Los Angeles, which has been turned into a makeshift memorial dedicated to the late pop icon.

Members of the Jackson family – including Joseph and LaToya – have been seen driving in and out of the compound where it is believed they are busy formulating a funeral for the singer.

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