Essex Police are warning drivers to be vigilant after concrete blocks, wood and barbed wire appear to have been deliberately left in roads in Tiptree.
The items have been left on unlit sections of road in the dark and caused thousands of pounds of damage to four cars and a bus.
There have been at least 12 reports between Sunday December 20 and Wednesday December 30.
Chief Inspector Nick Lee said: “We have released pictures of debris that has been recovered, and dashboard video footage supplied by one victim, which show just how dangerous this idiotic behaviour is.
“I’d like to thank people for contacting us and am continuing to appeal for anyone with information to get in touch. I also urgently need to speak to anyone else who has cleared these objects from the road and still have them in their possession, as they could assist our investigation.”
Police urgently want to trace two suspects seen throwing concrete onto the B1022 Colchester Road on 29 December at 9.28pm.
They were seen in woods and ran off when approached by members of the public.
They were a white man, aged 20 to 30, wearing camouflage trousers and an orange and grey top, and a woman, aged 20 to 30, wearing grey and black clothing including leggings.