A man was found bleeding from his face in an industrial estate in Ribbleton after being abducted.
Preston Police say the 18-year-old was taken from Walton Avenue, Penwortham.
Around 10.15pm on Thursday 28 February he was forced into the back of a silver BMW estate car at knifepoint.
The victim was driven to an industrial estate off Longridge Road.
He was slashed in the face and left on the estate, and was found by a lorry driver who called for help.
Detective Sergeant Jerry Sturgess, of Chorley CID, said: “We are appealing for information following this vicious attack.
“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.”
Three men, aged 26, 30 and 32 from Preston, have since been arrested in connection with the incident. All three have been released under investigation while police enquiries continue.
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Anyone with information about the incident is asked to contact police as soon as possible on 101, quoting log number 1572 of the February 28th. Alternatively, they can contact independent charity Crimestoppers anonymously on 0800 555 111 or online at http://socsi.in/TPbXb. No personal details are taken, information is not traced or recorded and you will not go to court.