The Commonwealth Games was hit by a new crisis today with up to 15 swimmers on the England and Australian teams being hit with a stomach virus, possibly from water at the aquatics centre.

England's swim team doctor said today that between eight and 10 athletes were ill. Australia has reported at least six swimmers sick.

Games Federation president Mike Fennell said officials will test both the main pool and the warm-up pool at the Dr S.P. Makherjee Aquatic Complex in Delhi.

Asked if the swimming, which began its fourth of six days today, might be cancelled or moved if tests showed the pools were unsafe he said: "I would not like to speculate about this immediately. If there is something unsafe, you cannot swim in that water. It is a matter we have to deal with a great deal of urgency."

There was no immediate indication of any testing being undertaken at the aquatic centre today. The synchronised swimming event was underway in the dive pool, while the main pool was idle ahead of the early evening's finals session.

During the meet, photos taken by an underwater camera in the main pool were mostly murky.

An Australian swim team spokesman said "about a half-dozen" swimmers had been affected by stomach problems. "Our doctors are looking into it ," he said.

England team spokesman Caroline Searle said between seven and 10% of England's 541-strong delegation had been affected by a "mild 24-hour stomach condition."

"That's lower than we anticipated," she said. "Separately we have asked for reassurances as to the water quality at the aquatics venue. We're not complacent and continue to reinforce the need to be vigilant in areas like hand hygiene."

Concerning the swimmers, Ms Searle said "we will look at that, but it's really a matter for the organising committee."

The games bring together more than 6,000 athletes and officials from 71 countries and territories. But construction delays, corruption allegations, concerns about security and heavy monsoons put preparations for the games way behind schedule, with complaints about unfinished and filthy accommodations in the athletes' village embarrassing the hosts.

To make matters worse, three Ugandan team officials were injured in an car accident at the entry to the athletes' village and spent 24 hours in hospital under observation before being released yesterday.

Uganda won its first gold medal of the games later Wednesday in the men's 5,000 on an athletics track that was still being repaired just hours before the first events started.