About one in six Queensland drivers allegedly tested positive for illegal drugs during a four-month police operation, with drivers in the state's north the worst offenders.
Operation Tango Anaconda, which ran from March to June, focused on deterring drug driving offences through high visibility random drug testing.
Over the course of the operation, 21,787 tests were conducted with 3,892 drug drivers detected.
Drivers in the northern police region, which includes Cairns, Cassowary Coast, Tablelands, Mt Isa and Townsville, tested positive on about one in four occasions.
They were followed by about one in five drivers in the southern region, which encompasses the Darling Downs, Ipswich, Charleville, Dalby-Burnett, Longreach, Roma and Pine Rivers.
About one in six drivers intercepted in the Brisbane Region tested positive, and about one in six tested positive in the south eastern region, which includes Gold Coast and Logan.
The lowest rate of drug driving offences was detected in the central police region, with about one in seven testing positive to drugs. Central includes Bundaberg, Gladstone, Gympie, Mackay, Maryborough, Rockhampton and Sunshine Coast.
It is unclear how many tests were done in each police region.
Acting Inspector Paul Algie said it was disappointing to see this behaviour.
"It's disappointing that there are people out there who think it's acceptable to be out on our roads while they are under the influence of illicit drugs," Mr Algie said.
"The consequences of drug driving are very serious. In the past decade we have seen around a 50 per cent increase in drug presence in fatal crashes and we know drugs are a major causal factor in 10 per cent of crashes Australia-wide.
"Many more Queenslanders could have died or been seriously injured on our roads if police didn't take action."
Mr Algie said police would continue to be out there targeting these dangerous behaviours on the roads.
"We'll continue to encourage motorists to make smarter decisions by taking them off the road.
"Expect to see police anywhere, anytime targeting drivers who are making the wrong choices.
"Every decision you make behind the wheel counts."
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