Motorists have been warned that a bus and tram "gate" installed in Sheffield to speed up public transport journey times is being monitored by CCTV.
Sheffield City Council said drivers faced a £60 fine if they did not observe the Glossop Road restriction.
Such gates allow buses and trams to bypass congested sections of road.
The council said about 3,000 public transport users were being delayed by the illegal use of the gate between 5pm and 6pm each weekday.
Camera enforcement is already used at other such gates in the city.
Kevan Butt, parking services manager, said: "There are new signs, a new surface showing where the gate begins and ends and we've been issuing warning notices to motorists passing through the gates illegally for the last two months."
The council said before the warning notices were issued, about 440 vehicles were using the bus and tram gate illegally each day during the evening period.
It said that over the past two months about 770 warning notices had been issued, which showed there had already been a decrease in the number of people flouting the restrictions.
Drivers who use the Glossop Road gate between 1600 BST and 1830 BST will receive a penalty charge notice in the future.
Bus and tram gates can also be used by cyclists and the emergency services.