The world was in shock today after the death of King of Pop Michael Jackson following a suspected heart attack at his home in Los Angeles.

Tributes from the world of music, film and celebrity have flooded in as the pop star’s fans posted messages on websites to express their grief.

Paramedics were called to the 50-year-old singer’s Holmby Hills home yesterday and he was taken to the UCLA medical centre but was pronounced dead at 2.26pm – 10.26pm BST. His brother, Jermaine Jackson, said: “We believe he suffered a cardiac arrest at his home, however the cause of his death is unknown until the results of the autopsy are known.

“The personal physician who was with him at the time attempted to resuscitate him.”

The self-styled King of Pop was due to perform 50 farewell concerts in London this summer, bowing out on an illustrious music career spanning several decades while aiming to restore his fortunes.

A spokesman for the hospital said: “When he arrived at hospital at approximately 1.14pm a team of doctors including emergency physicians and cardiologists attempted to resuscitate him for a period of more than one hour, they were unsuccessful.”

TV footage showed a rescue helicopter flying the star’s body to a waiting ambulance.

A post-mortem examination was expected to take place later today, Los Angeles Coroner’s Office spokesman Fred Corral said.

Among the first to express their grief was Jackson’s first wife, Lisa Marie Presley, who said: “This is such a massive loss on so many levels, words fail me.”

Sir Paul McCartney, who collaborated on tracks with Jackson in the 1980s, said: “It’s so sad and shocking. I feel privileged to have hung out and worked with Michael. He was a massively talented boy-man with a gentle soul. His music will be remembered forever and my memories of our time together will be happy ones.”

Jackson leaves three children, Michael Joseph Jackson Junior, Paris Michael Katherine Jackson and Prince “Blanket” Michael Jackson II.

Jackson, who spent time living outside the US since his 2005 acquittal on child molestation charges, last toured 12 years ago. Fans today were waiting to hear whether they will receive refunds for his 50-concert residency at London’s O2 venue.

During his career the singer sold an estimated 750 million records worldwide, with Thriller becoming the biggest selling album of all time.

• How will you remember Michael Jackson? Did you have tickets for one of his London concerts, or did you see him perform in Britain on one of his world tours? Tell us what he meant to you in the comment box below, or email us through this link.