Michael Jackson’s sudden death last night has left UK tour operators, who were offering packages to his upcoming concerts, desperately trying to find out more information from concert promoters.

The 50-date run at the O2 Arena in London, which was due to begin on July 13, was the fastest-selling tour in history with 40,000 tickets sold every hour.

Thomson Experience, Keith Prowse Attraction Tickets and Superbreak were all offering packages including tickets to the show, while the Manchester Airports Group teamed up with Balkan Holidays to offer Jackson tickets as an agent incentive.

A Thomson Experience spokeswoman said the operator is trying to contact concert promoters AEG Live to find out how to go about refunding tickets.

However, she added the operator would offer refunds on accommodation sold as part of the package, although it is also expected that many customers will replace their Jackson tickets for those to other West End shows.

Superbreak sales director Ian Mounser said it has already posted information on its agents’ website detailing what customers with Jackson packages are entitled to.

He added: “If clients decide to cancel, refunds will be given, or monies can be transferred to different bookings.”

However, an ABTA spokeswoman has confirmed that tour operators are liable for refunding the cost of the entire package.

In May, Jackson postponed the first four concerts claiming he needed more time to rehearse.

Rumours were already circulating that at the age of 50 and with failing health, Jackson simply wasn’t up to performing the gruelling schedule. Despite this, his death has come as an unexpected shock.

Tickets for the global superstar’s extravaganza, which was due to run over nine months, immediately cropped up on the internet with a resale value of more than £1,000.