Twice as many young drivers are being caught drink-driving than older motorists during a police campaign to tackle the problem.

So far this month, one in 10 drivers stopped by police in Oxfordshire have failed the breath test. And 21 per cent of drivers under 25 were over the limit, compared with 11 per cent of older motorists.

Overall, 13 per cent of all drivers in the county have so far failed breath tests and police have warned that the crackdown will continue.

Supt Mick Doyle, head of Thames Valley's roads policing department, said: "It's extremely disappointing that some drivers are still choosing to ignore our warnings and think it's acceptable to put themselves and other road users at risk.

"The campaign is running until September 1, and it would be great to see a decrease in the figures in the last two weeks.

"Drivers should remember, however, that roadside breath tests are carried out throughout the year. Officers are also required to test every driver involved in a collision, regardless of the time of day and whether they have been drinking or not."

Police have stopped and breath-tested 167 motorists in the county since the campaign began at the start of this month.

At the halfway point last week, 22 - or 13 per cent - were over the limit. Across Thames Valley as a whole, 13 per cent of the 664 drivers stopped tested positive for excess alcohol.