A collision has taken place between a car, motorcycle and a van at Denton Crossroads this afternoon.
Emergency services were called to the crash on the A607 Grantham Road, Denton at 3.30pm.
The motorcyclist, believed to be a man, was seriously injured and has been flown to Queens Medical Centre, Nottingham by Air Ambulance.
The road is presently closed at Denton Crossroads and will be for some time whilst investigating officers try to establish what happened.
Anyone who witnessed the crash is asked to contact Lincolnshire Police via the non-emergency 101 number, quoting incident number 215 of May 6
Alternatively call the Collision Witness Hotline on 01522 558855, for the information of Sergeant Ady Wootton.