It was reported a Polaris Ranger vehicle pulling a trailer had fallen into a river when a bridge collapsed, the Lancashire Post reported.
Eleven people were in the ranger vehicle and trailer at the time of the incident.
Sadly, one man suffered fatal injuries and was pronounced dead at the scene.
A second man suffered a serious head injury and was taken to Royal Preston Hospital for treatment.
A third person has suffered a serious back injury and was taken to Royal Lancaster Infirmary. Others who are injured have also been taken to Royal Lancaster Infirmary.
Emergency services including police, ambulance crews, fire crews and mountain rescue responded to the scene.
Road closures remain in place today (Wednesday, January 19) and are expected to continue for some time.
Police said the people in the vehicles were from a "shooting party" who were "travelling on private land" and were returning to the farm when the bridge collapsed.
An investigation into the circumstances around the incident is underway and the Health and Safety Executive has been informed.
Det Insp Kirsty Wyatt, of Lancashire Police, said: “My thoughts are very much with all those involved in what is a very sad and tragic incident.
"One man has sadly died and a number of people have suffered serious injuries.
"At this time we believe the vehicle was pulling the trailer, containing a number of people, when a bridge gave way. Those people were then thrown from the vehicle and trailer.
"Our investigation is at very early stages and enquiries are ongoing to establish what happened."
Anyone with information which can help police can call 101 quoting log 0953 of January 18.
The Health and Safety Executive, North West Ambulance Service and Lancashire Fire and Rescue Service have been approached for further details.
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