GOING on an 'alco-bender' in Alcobendas doesn't pay – but being breathalysed can, thanks to a new incentive launched by the police in the town just outside Madrid.

Partygoers driving home actually present themselves to give a breath test – because they can get free petrol out of it.

Police explain that they are concentrating their efforts in the parts of town where the most bars, restaurants and nightclubs are found, and breathalysing as many drivers as they can.

Those whose results come up negative – proving they are sober behind the wheel – will be given a card which is stamped.

By the time they have taken four consecutive tests, all of which have come up with negative, or sober, results, they will be given a 20-euro voucher to spend on petrol.

Other gifts, such as soft drinks and T-shirts, are also handed out.

Officers say the incentive is working even better than the threat of fines, criminal action and the loss of their licences.

The campaign started on Saturday night in Alcobendas (Madrid) in the popular Avenida de España area.