A group of men targeting lone women drivers in order to make fraudulent insurance claims across the UK are now feared to be operating in Sheffield.
The Insurance Fraud Bureau and police are warning motorists to be aware of the scam which has been reported in a number of counties this week.
The scam involves a car full of men suddenly braking on a roundabout despite there being no traffic oncoming, causing a crash.
Around 150 city motorists have now taken to Facebook to voice their concerns and describe how some have fallen victim to this in Sheffield.
One driver said she feared for her life when it happened at around 70mph and others told how the scammers quickly become angry and start banging on their windows.
Charlotte Ball said: "This happened to me coming out of Meadowhall. The car in front of me braked suddenly although the lights were at green. I luckily managed to break within an inch of his car. The guy was going off mad at me that I'd whacked his car and he demanded my details."
She added that she had to call police after he "blocked me in and then proceeded to bang on my window angrily."
Andrew Kerslake said: "There was a white Vauxhall combo van that I think was doing this around Darnall on Saturday. Pulling out in front of people and cutting into traffic and then braking heavily."
Danny Fieldhouse added: "They been doing this for years especially up Wincobank and the Meadowhall area. The driver doesn't claim but has a car full of passengers and he takes a cut from all their claims."
Liz Southwell feared for her life when it happened to her last week when travelling down the A1 at around 70mph.
She added: "This guy pulled in front of me and slammed his breaks on for no reason. I managed to stop then he put his foot down and drive off. Why would anyone do that especially going that speed. He could have killed people not just me."
Suzanna Kitchen explained how a black Audi stopped suddenly in front of her at a roundabout near Killamarsh and Meadowhall. The man then "started shouting things out of the window."
Susan Howgate described the crime as "terrible" and called for tough jail sentences for scammers who are "terrorising innocent motorists."
These incidents come after the police issued a warning about ‘cash for crash’ incidents back in February this year.
Police said dashcams and taking pictures as evidence - when safe to do so - is recommended. Incidents can be reported to the Insurance Fraud Bureau on 0800 4220421.