Fans of the rock band the Kaiser Chiefs are demanding an explantion after being told their online bookings will not now be honoured.

Computer systems at the booking office went into meltdown as thousands of fans tried to obtain tickets via the internet when they went on sale last Thursday.

Meanwhile, large queues formed at the Welcome Centre in the Sea Terminal for tickets to the concert in August.

It's emerged tickets had sold out by the time the online system was rebooted, and although applicants were sent emails confirming their orders, they have been told the bookings cannot be honoured.

The Department of Tourism and Leisure, which handled the bookings, is due to make a statement later.