A teenager was slashed across the face after being abducted at knifepoint and forced into a car, police said.
A lorry driver found the 18-year-old with "serious life-changing injuries" dumped on an industrial estate off Longridge Road, Preston on 28 February.
Police said the man had been ordered into the back of a silver BMW estate in Walton Avenue, Penwortham at 22:15 GMT.
Three Preston men, aged 26, 30 and 32, were held before being released pending further inquiries by Lancashire Police.
Det Sgt Jerry Sturgess said: "The victim received immediate hospital treatment but will have serious, life-changing injuries.
"We believe there will be someone - or several people - who have information about this incident, including the movements of the car and its occupants, and we would urge them to get in touch as soon as possible."