Police in Wales carried out over 11,000 breath tests

Over 5.5% of people tested during Operation Sherry this year were found to be over the limit - compared to 4% of drivers tested last year.

Officers caught 638 people after carrying out more than 11,550 breath tests between 5 December and 2 January.

All four Wales police forces were involved in the campaign.

There were also 20 arrests for driving under the influence of drugs - 10 in south Wales, five in north Wales, two in Dyfed-Powys and three in Gwent.

South Wales Police caught the highest percentage of drink drivers - with 267 out of 3,622 people testing positive. Just over a third were drivers aged 25 and under.

'Unacceptable'

Police said many tests were carried out during routine roadside checks or following road crashes.

Information from members of the public was also used to target operations.

Sergeant Nigel Whitehouse, from South Wales Police, said the use of intelligence and more resources had helped increase the number of arrests in his force area.

He told the BBC News website: "We were lucky in our force to secure additional funding which enabled us to bring in officers on overtime.

"Their sole purpose was, from intelligence gathered, to go and get drink drivers."

OPERATION SHERRY Positive tests: South Wales Police - 267 out of 3,622 tests (7.3%) Gwent Police - 139 out of 2,307 tests (6%) Dyfed-Powys Police - 106 out of 2,159 tests (5%) North Wales Police - 126 out of 3,462 tests (3.6%)

Chief Superintendent Graham Davies, from South Wales Police, which led the all-Wales campaign, said it was "unacceptable" that more than 600 drivers had put their own and others' lives at risk.

He said: "Drink-driving will not be tolerated and the four Welsh forces will continue to work together to take drink-drivers off the road.

"We would like to thank those members of the public who played a vital role in this campaign by providing information which enabled us to carry out a more focused operation."

Many of those caught have already appeared before the courts and have been banned from driving and received fines.

Christopher Woolley, Chief Crown Prosecutor for South Wales, said: "If convicted, offenders face the full extent of the law and the real risk of imprisonment, long disqualifications and hefty fines for their behaviour.