A national police operation to tackle drink and drug driving has seen over 6,600 drivers arrested, with clear evidence the problem of drug driving is on the rise - prompting the Home Office to warn it will be launching a clampdown.

Merseyside police recorded the highest number of drug driving arrests during the initiative, making 469 arrests for drug driving, compared to 191 for drink driving.

Other areas which recorded more drug driving arrests than drink driving include Greater Manchester (199 drink / 243 drug), Hampshire & Isle of Wight (131 drink / 156 drug), North Wales (67 drink / 90 drug), Sussex (115 drink / 146 drug) and Thames Valley ( 240 drink / 245 drug).

However, despite the Home Office last week pledging to crackdown on the problem, a drug testing distributor warned this week that without additional police funding the problem will persist.

Ean Lewin is the MD of D.tec International, UK distributor of DrugWipe, which is used by all police forces in England, Scotland and Wales as well as hundreds of corporate clients to test for drug driving.

He said: ”If the Home Office are serious about clamping down on this behaviour and want to address a growing drug drive culture, they must provide additional funding to support cash-strapped police forces with specialist roads policing which is desperately needed to address the problem.”

The police campaign, which took place over the Christmas period, saw every police force engaged in increased breath testing through targeting vehicle stops in hot spot areas and intelligence-led patrols.

This is the second annual national operation, known as Op Limit, to coordinate this activity across the country, bringing together all police forces to target drink and drug drivers.

The police conducted 49,812 breath tests of which 9.5% were positive, failed or refused. Nearly 7,000 (6,846) drug tests were conducted with 48.5% of those testing positive.

Men featured large in the list of offenders, making up 84% of drink or drug driving offenders, of which 74% were 25 years old or over.

Of the 6,616 arrests made for drink and drug driving offences,1,589 individuals were charged.

Chief Constable Jo Shiner, National Police Chiefs council lead for roads policing, said: “Drink and drug driving is responsible for many serious and fatal collisions every year and it is completely avoidable.

“Policing has always taken a robust approach to removing drink and drug drivers from our roads and as long as people continue to undertake this dangerous behaviour, we will continue to make stopping it a core roads policing priority.”

Chief Superintendent Marc Clothier, National Police Chiefs council operational lead for Op Limit, added: ”This national collaboration around Op Limit has been really successful and we’ve seen a wide range of tactics employed by forces around the country.

”We’ve also seen a number of innovative tactics such as the sending of Christmas cards to known offenders, reminding them that we are undertaking proactive patrols and underlining the dangers of drink and drug driving.

“While numbers of positive tests are very slightly lower than last year, far too many individuals still make the selfish choice to drive under the influence or drink or drugs.

“We know that both alcohol and drugs have a significant impact on reaction times, control of the vehicle and awareness of what’s happening around you so it is absolutely not worth risking your life and the lives of other road users.”