Powerboats were only one lap into qualifying when it was called off

Some of the world's top powerboats had been carrying out last minute practice runs in preparation for the Honda Powerboat Championship on Sunday.

A fire boat was brought in to disperse the dolphins and qualifying restarted after about an hour after harbour authorities gave it the all-clear.

Organisers are now hoping the dolphins will stay away for the Class 1 finals.

Pied piper

Earlier, a race in the Honda 4-stroke series was also cut short when dolphins were spotted.

The dolphins were dispersed after a fire boat acted as a "pied piper", leading the dolphins out of the harbour by attracting them with the noise of its high-powered water pumps.

It will now be up to the harbour authorities to decide if the area is clear on Sunday before proceeding with the finals.

Gavin Parsonage, 24, driver of Honda 4-stroke boat Negotiator, said: "I've never seen anything like it.

"You would have thought the dolphins would have been scared of the boats, but they didn't seem to care.

"There must have been about 30 of them."

They have a right to the bay as much as anyone else Class 1 spokesman Nigel Quilter

The dolphins were spotted again after one lap of racing in the bigger Class 1 boats.

Class 1 spokesman Nigel Quilter said: "It nearly ruined the day for thousands of people, but the dolphins must be respected.

"They have a right to the bay as much as anyone else."

Johnny Wymark, one of thousands of onlookers at Plymouth Hoe, said: "It's a crusher. I've come from Bigbury to see this and it's ruined my day, but it's good that organisers respect the dolphins.

"I'll be back tomorrow and hopefully the dolphins will be elsewhere."

The Honda Powerboat Championship pits 10 of the world's most powerful boats against each other in a course of 117 miles over 18 laps.