Twenty eight people had to be rescued from a rollercoaster at Alton Towers theme park on Sunday afternoon.

The Corkscrew ride failed to complete its circuit, trapping the visitors in its loops for 90 minutes.

A spokesman for the park said no one was injured and an investigation is underway into what went wrong.

The same rollercoaster failed in 1997, trapping four members of staff as they carried out a routine test ride. They had to climb off using a ladder.

The Corkscrew ride, now in the dinosaur-themed Ug Land section of the park, was introduced to Alton Towers in 1980.

The park calls it its first "true thrill ride", and it was the first in the UK to invert riders twice in quick succession.

But enthusiasts nowadays say it is old-fashioned and offers a very average ride.

The Staffordshire park is the most-visited theme park in Britain, with 40 million visitors since the Corkscrew was introduced.