More than 40 cars have now been targeted by 'irresponsible' vandals throwing items at passing cars.
The spate of incidents of criminal damage have occurred along the Suffolk and Norfolk border in various villages and towns along the A146, A143 and the B1062 since police officers received the first report on Friday, May 24.
Earlier this week, Gemma Wiles, 42, from Harleston, warned someone could be killed after her Skoda car was struck by an object and written off near Thorpe Abbotts, saying: "I want to warn other people to be careful, at the end of the day this could kill someone. The people who are doing this need to be caught."
That warning followed taxi driver David Thompson, who was hit by a brick on June 1.
He said: "They might think they are having a bit of fun but that fun might kill somebody."
Now, officers have revealed details of a further six incidents reported this month.
At around 11pm on Sunday, June 2, a Ford Fiesta was damaged by an item thrown from another car on the A146 heading towards Lowestoft.
An Audi S3 was being driven along the A143 near Ellingham towards Bungay at 10.15pm on Thursday, June 6, when it was hit by what is believed to have been a rock, causing damage to a wing mirror and wind deflector, as well as denting the body and damaging the paintwork.
The following day, at 5pm, a "rock-type object" was thrown at a Vauxhall Astra on the B1062 at Mettingham, causing significant damage to the off-side wing, police confirm.
Shortly afterwards, at approximately 5.40pm on the A143 at Beccles, the driver of a BMW 320 reported a large object being thrown from one of two passing cars. The object bounced off the bonnet and shattered the windscreen on the passenger side, covering the passenger.
On Saturday, June 8, a motorist was driving along the A143 between Earsham and Wortwell when they heard a loud bang as their Vauxhall Insignia passed a vehicle in the other direction.
A piece of rubble was found the following morning wedged behind a damaged numberplate.
Later that night a motorist was driving along the A146 northbound at Hales, near to the petrol station, when a rock, stone, or brick was thrown at the front of the Peugeot 3008, denting the bonnet, scratching the front and damaging a parking sensor.
Officers from both Norfolk and Suffolk Police have been carrying out a number of overnight patrols and are exploring the possibility the incidents are linked.
Inspector Liz Casey, from Lowestoft Police, said: "These incidents had the potential to cause road traffic collisions and, in turn, serious injury or damage.
"All of the incidents have occurred during the evening or overnight when visibility will be reduced for motorists so it is fortunate that no one has so far been hurt and although the damage will be costly to victims, it has not cost them their lives.
"Such behaviour is extremely irresponsible. Throwing any item into traffic puts lives at risk, and anyone found to be doing so will be firmly dealt with.
"Anyone that is caught throwing objects at vehicles could also personally face a criminal conviction for not only criminal damage but could also result in other offences including, among others, causing danger to other road users."
Officers are urging motorists to report incidents as soon as possible with the location, direction of travel and as much information as possible to assist with enquiries.
Anyone who has been a victim, or has information or dashcam footage of these incidents, is urged to contact PC Andrew Roberts at Suffolk Police or PC Andy Barkway at Norfolk Police on 101.
The crime reference numbers for the six incidents reported here are: 37/32705/19, 36/38379/19, 37/33033/19, 37/32785/19, 36/38987/19, 36/38984/19.
Alternatively, call Crimestoppers anonymously on 0800 555 111.
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