A Polaris Ranger pulling a trailer plunged into a river after a bridge in the Moor Lane area collapsed at around 4.25pm on Tuesday (January 18).
Eleven people were in the vehicle and trailer at the time of the incident as part of an organised shoot, police said.
Brian Harwood, 73, from Penrith, Cumbria, suffered fatal injuries and was pronounced dead at the scene.
Two other men aged in their 60s and 70s are receiving treatment in hospital for their injuries.
Following further investigation, three men were arrested on suspicion of gross negligence manslaughter today (January 20).
They were a 55-year-old man from Preston, a 57-year-old man from Lancaster and a 52-year-old man from Lancaster.
They have since been released under investigation.
Det Insp Mark Dickinson, of Lancashire Police's Force Major Investigation Team, said: "This investigation remains in its early stages and we are conducting a number of enquiries to establish exactly what has happened, including whether any criminal offences were committed.
“Three men have been arrested and are assisting police with our enquiries.
"They have now been released, but remain under investigation."
He added: "We are supporting the families of those involved and working with partners, including the Health and Safety Executive, to establish what caused the bridge to collapse.
"Our thoughts remain with Mr Harwood's loved ones and everyone affected by this tragic incident."
Anyone with information about the incident can contact police on 101, quoting log number 0953 of January 18.
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