Victims have their drink spiked with a so-called date rape drug

The figure came to light after a senior doctor at Morriston Hospital in Swansea said he can see as many as 10 victims of so-called date rape drugs in one weekend.

And a counselling organisation has said that south Wales is a hotspot for drug-related rape and sexual assault where the victim has their drink spiked.

The Roofie Foundation, which offers a telephone counselling service to victims of drug rape, says the number of cases it has dealt with from Cardiff as well as Swansea is on the rise.

Safe drinking practice: Do not leave a drink unattended If drinking from a bottle, keep your thumb over the top Take your drink with you to the toilet Do not accept drinks from strangers

More than 350 people in Wales contacted the Yorkshire-based counselling service the Roofie Foundation in 2002 to say they have been sexually assaulted after having their drink spiked.

The figure was a rise of almost 100 on the previous year, yet just 15% said they had reported the incident to the police.

Victims out drinking in pubs or clubs, or even at parties, found their drink was targeted with so-called date rape drugs such as GHB (gamma hydroxybutyrate) or the sedative rohypnol.

Roofie Foundation Chief Executive Graham Rhodes said he expected the number of attacks during 2003 to be even higher.

"The Swansea/Cardiff area has been one of our main concerns for a long time. We must have had 22-25 cases a week from February to May this year.

"We were getting so many reports that we did contact the police in that area and south Wales does seem to be getting more convictions than other areas."

Police believe incidents of date-rape are under-reported

GHB is also known as "liquid ecstasy" and is taken recreationally by some drug users because it can mimic the effects of alcohol without bringing the same kind of hangover.

But people who are given it unknowingly find the drug disappears from their system in as little at 12 hours, making it harder to prove that they were in fact drugged and not just very drunk.

However Mike McCabe, consultant in accident and emergency medicine at Swansea's Morriston Hospital, said victims of GHB and other such drugs suffered emotionally in addition to the physical damage.

"These are drugs that people can't see or taste.

"The real problem with them is their psychological effect. People find there is a gap in their memory and they can't find out what happened."

Last month, North Wales Police warned young clubbers to be on their guard after a young woman had her drink spiked in a Llandudno nightclub

In May this year, a west Wales man who admitted sexually assaulting a woman he had drugged with GHB was jailed for ten years.

Last Christmas, Wales' four police forces distributed two million beer mats warning of the danger of date-rate drugging during the festive season.