Drivers are being urged to avoid the area after a serious crash near Higham Ferrers.
Police, fire and ambulance were all called to the crash involving two cars on the B645 Chelveston Road just after 8am today (Monday).
A spokesman for Northants Police said: “Please be aware that the B645 Chelveston Road is currently closed between the A6 and Bidwell Lane due to a serious collision.
“Motorists are asked to find an alternative route while emergency services deal with the collision.
“However, anyone due to attend the event at Rushden Golf Club can still gain access via Chelveston or Caldecott.”
The spokesman added that the crash happened near to the Moulton College campus in Higham Fererrs.
A spokesman for the Magpas Air Ambulance service, which attended the crash, said: “The Magpas enhanced medical team assessed a patient in his late teens who had sustained severe head injuries and placed him into a medically induced coma at the scene (providing him with A&E level care), before accompanying him to Coventry Hospital via land ambulance.
“The patient was in a stable condition upon arrival.”
The spokesman added that they also assessed a second man in his 40s who hadn’t suffered any life-threatening injuries and was left in the care of the EMAS ambulance service.
Police are appealing for witnesses following the crash.
A police spokesman said: “The collision happened shortly after 8am this morning when a silver Ford Fiesta, travelling towards Higham Ferrers, for reasons yet unknown, crossed onto the opposite carriageway and was in collision with a grey Skoda Octavia travelling in the opposite direction.
“The driver of the Fiesta, driven by an 18-year-old man, was taken to University Hospital Coventry with serious injuries.
“The Skoda driver, a 45-year-old man, was taken to Kettering General Hospital.”
Witnesses to the collision or anyone with information about it is asked to contact the serious collision investigation unit on 101 or via the Drive Watch Hotline on 0800 174615, quoting incident number 86 of 9/4/18.