Michael Jackson to add concerts after sellout

The 50-year-old singer has been a virtual recluse since his acquittal on child abuse charges in a 2005 trial, his last full set of live concerts was 12 years ago and he has not recorded an album of new music since "Invincible" in 2001.

Last week he announced his long-awaited comeback at London’s O2 Arena, where he plans a Las Vegas-style "residency" with a series of 10 concerts beginning on July 8.

"The pre-sale 10 shows at The O2 that went on sale this morning at 7 a.m. have already sold out," said Outside Organization, the PR company representing promoter AEG Live.

"Due to the incredible level of interest, Michael Jackson has allowed AEG Live to add extra shows."

It was not immediately clear how many concerts would be added. The website of music magazine Rolling Stone reported 12 extra concerts had been booked.

AEG Live said last week it may extend Jackson’s London series and launch gigs elsewhere in the world if the demand was there.

Jackson is still the "King of Pop" to his legions of fans despite his sometimes bizarre behavior and appearance in recent years. He has sold around 750 million records, won 13 Grammys and is regarded as one of the biggest pop acts of all time.