The Los Angeles coroner's office says it may be weeks before it is known exactly what killed pop star Michael Jackson.
Coroneroffice spokesman Craig Harvey told reporters late Friday that anautopsy of Jackson's body indicated no signs of external trauma or foulplay. But, he says the office is deferring determination on cause ofdeath for now.
Harvey says additional toxicology and pulmonarytesting is needed before a determination can be made. He says thetests usually take four to six weeks to complete.
Late Friday, the coroner's office said the body of the international pop star was released to his family.
Meanwhile,Los Angeles police are seeking to question Dr. Conrad Murray. He waswith the singer when he died suddenly on Thursday.
Police towedthe doctor's car, which was at Jackson's house, and say they arelooking for medications that could be related to the death.
Jackson was pronounced dead Thursday at the UCLA Medical Center after suffering cardiac arrest at his Los Angeles home.
WhiteHouse Spokesman Robert Gibbs said Friday that U.S. President BarackObama called Jackson a "spectacular performer" and a "music icon," butsaid the president also noted parts of the singer's life were "sad andtragic."
Jackson died about two months before his 51stbirthday, and just before July's scheduled launch of a series ofcomeback concerts in London. Tickets for his London shows, offered inMarch, sold out in minutes.
Jackson had been rumored to be inill health for years, but the promoters of his London shows say hepassed a recent medical examination.
The singer, dancer andsongwriter became famous as a child in the 1970s while performing withhis brothers in The Jackson 5 pop group. He went on to anunprecedented solo career, selling more than 750 million records,including the best-selling albums , becoming adynamic live stage act, and pioneering the music video genre.
Jacksonwas dogged by controversy in his later years. He was acquitted in achild-molestation trial in 2005 and struggled with financial problems.He was the subject of countless tabloid newspaper stories about hiseccentric behavior, close relationship with children and multipleplastic surgeries that led to a dramatic change in his appearance.