Anti-drink spiking devices were being handed out last night as police launched a new initiative aimed at reducing the amount of sexual offences in the city centre.

Groups and individual revellers were approached by volunteers in Centenary Square giving advice along with the anti-spike devices and sweets and leaflets carrying safety messages.

Police officers, volunteers from the NHS, the probation service, Street Angels and night marshals are working together on Operation Northdale – which has been running over the Christmas and summer periods for the past two years and has resulted in a 71 per cent reduction in the number of sex offences during those times.

Volunteer Rachel Hussain, a district nursing team support worker, said: “This is a really good initiative. We know how important it is to educate people of the dangers of drinking too much.”

The team will be stationed in the Kirkgate Shopping Centre on Saturday afternoons and out on the streets on Friday and Saturday nights for the next four weeks.

Officers will also be joined by taxi licensing officers targeting unlicensed taxis operating around West Yorkshire.

Inspector Jon Morgan of the West Yorkshire Police local policing department, said: “With the summer months upon us, more people tend to hit the towns and city centres to enjoy the warm weather.

“While we want people to go out and have fun, we urge them to drink responsibly and not make themselves vulnerable through binge-drinking.

“It is vital that people look out for bogus taxi drivers and ensure that, when they do take a taxi, it is either pre-booked or is from a recognised rank.

“Operation Northdale has achieved some really positive results over the past two years and has demonstrated some fantastic partnership working with volunteer organisations such as Street Angels, and we hope this year’s drive will be even more successful.”

Laura Benazaize, 18, who was out in the city centre with friends, welcomed the operation.

She said: “I think the anti-spiking devices are good. I’ve got friends who have been spiked so I know the dangers. The devices should be put on drinks everywhere.”