Almost 50 vehicles across the UK are to be fitted with the latest technology for combating fuel fraud.
A new dye has been added to tax-rebated fuel which is intended for agricultural use, senior HMRC official Pat Curtis added.
A "world first" roadside check being introduced over the next three months will easily detect motorists who use discounted red diesel, the expert said.
He added: "This is ground-breaking technology. There is no other trial of these ... in vehicles like this anywhere else in the world.
"We attempt to be one step ahead of the organised criminal gangs."
The technology to analyse fuel is designed for use at the roadside or retail premises and is being installed on 49 testing vehicles throughout the UK.
Mr Curtis, the national oils lead for specialist investigations across the UK at HMRC, added: "We get a result, a very forensically correct result, within minutes at any of the sites that we visit."
He said the enforcement organisation would still carry out tests for the old markers.
The fraud has been worth around £400 million a year in lost tax revenues in Great Britain and £80 million in Northern Ireland, where the problem is particularly acute, the HMRC has said.
In April the new fuel marker was introduced in the Republic of Ireland, Northern Ireland and the rest of the UK after several years of trials.
Red diesel is cheaper than regular diesel and is intended for off-road agricultural use.
Organised crime gangs have established sophisticated laundering plants to remove earlier giveaway dyes.
In Northern Ireland, which shares an open border with the Irish Republic, the problem has been a long-standing one. Figures for 2012/13 indicated the illicit market to be worth 13% of the total.
The number of laundering plants dismantled in Northern Ireland trebled in 10 years, from 13 in 2003/04.
RAC fuel spokesman Simon Williams said: "The development of a new dye for tax-rebated red diesel and a mobile check to detect its illegal use is a major step forward in the battle against fuel fraudsters.
"Everyone should have to buy legitimate fuel from reputable sources and no one should escape paying duty, other than those the discounted fuel is intended for in the agricultural sector.
"Too much revenue has been lost to date from this illicit practice so this move should help to ensure everyone driving a road vehicle pays their fair share of duty.
"The environment should also be better off as this will hopefully put an end to the illegal dumping of hazardous chemicals used to remove the previous dye."