Nightclub security staff rushed to help a woman after her drink was spiked in an Oxford pub.

The woman was dancing in the Chicago Rock Cafe, in Park End Street, when she started to feel queasy.

After failing to catch the attention of security staff at the venue, she made her way to the Park End nightclub nearby.

The woman, who has not been named, began vomiting and told door staff she was concerned that drugs had been slipped into her drink by a man she saw acting suspiciously.

The door staff found the man, who was carrying a number of pills designed to treat diabetes.

Medical experts from NHS Direct said the pills could cause drowsiness, loss of control, and nausea if used by non-diabetics.

The man was arrested in connection with supplying drugs, but later released without charge.

Lucy Ferguson, a spokesman for Oxford Police, said: "The man was released when it was decided the investigation could not be taken further."

Police warned people never to leave drinks unattended.

Last year, a woman claimed her drink had been spiked while she was in Chicago Rock Cafe. Two years ago, at least seven women had drugs slipped into their drinks at pubs and nightclubs in Banbury.

Luminar Leisure, which owns Chicago Rock Cafe and Park End, said security staff were trained to deal with drug-related problems.

Spokesman Jon Brett said: "Drugs are not generally a problem at our venues and we have a strict no-drugs policy."