Drivers have tested positive for a range of illegal and prescription drugs

A total of 136 drivers tested positive for drugs last year, an increase of 54 on the previous year.

Tests on the drivers revealed a range of drugs including cannabis, ecstasy and amphetamines.

Chief Inspector Brian Kee said there were still motorists out there who by taking drugs and driving were "totally irresponsible".

Mr Kee revealed the figures on Wednesday at an event marking the first anniversary of an anti drug driving road safety campaign.

"The message is getting across but there is still a hard core of motorists out there who are totally irresponsible, who put their own lives, the lives of their passengers and the lives of other road users at risk by taking drugs and getting behind the wheel of motor vehicles," he said.

"When blood was analysed from 86 drivers or motorcyclists killed on the roads last year, it was found that 10 drivers and two motorcyclists (14 per cent) had consumed impairing drugs.

That figure could rise, as some tests still need to be completed.

Chief Inspector Kee added that prescription drugs are as likely to impair someone's ability to drive so people must read the instructions of their medication carefully.

"I can assure anyone tempted to take impairing drugs and drive that the police service is better prepared than ever to detect them and put them before the courts."