Young swimmers who were struck down with a sickness bug while training on a Spanish island were last night back in training at the University of East Anglia Sportspark.

The City of Norwich Swimming Club took 30 schoolchildren and students to Mallorca on Easter Monday to train on the island.

But, when a mystery virus swept through the town of Colonia Sant Jordi, where the club was staying, almost half the group fell ill and one 12-year-old boy whad to stay in hospital overnight suffering from dehydration.

However, the dedicated young swimmers, aged from 11 to 17, flew back to London City airport on Monday and last night were back in the water at the Sportspark.

Club chairman Mark Bateman said: 'The important thing is that they are all okay. They're back in training this evening and they'll be back again early in the morning before heading off for school. 'They flew out on the Easter Monday and began to feel unwell on the Saturday. About 12 of the children were affected and one of them had to spend the night in hospital because they were dehydrated.

'It was just a 24 hour bug, but we just don't know where it came from. We have been assured that there will be test results coming through in the next seven days.

'It was good that it didn't happen earlier in the week, as they had the best part of a week of training before this happened.

'Even after they had it they wanted to get back into the pool, but we kept them out as a precaution.' Mr Bateman said the swim camp was the idea of head coach Alex Pinniger, who he said had transformed the club since his arrival.

Mr Bateman said the club had no qualms about returning to the island in the future, with the facilities at the Best Swim Centre considered some of the most impressive available.

He said one of the club members - Jessica-Jane Applegate - who was among the first 16 British swimmers selected for the Great Britain team for the London 2012 Paralympic Games, would be among those who will head back to the island for training.

The City of Norwich Swimming Club has some 1,300 members, ranging from young beginners in Norwich Penguins to elite competitive swimmers.

Further details on the club can be found at www.cityofnorwichsc.co.uk

dan.grimmer@archant.co.uk