Undercover police are posing as cyclists to try and catch drivers who overtake dangerously close in Manchester.
The traffic unit will wear body cameras to capture any offences and record the evidence to then alert the nearest police on patrol.
The move comes after police in the West Midlands took on a similar scheme where offenders were either prosecuted or educated on the proper conduct.
Manchester council and local cycling bodies have welcomed the crackdown by plain-clothed officers of Greater Manchester Police which has already begun in Tameside, Bolton and central Manchester.
Motorists should give cyclists a distance of 1.5 metres or the same distance as other vehicles when overtaking.
The police are warning motorists that the next cyclist could be a police officer and so they should be respectful of each other's space.
Offenders who refuse to engage with the police will be charged and fines or penalty points will be issued.