The firearms team and police officers arrived at West Pasture Farm, Barrowford, on Tuesday night, after a man was reported to have threatened an ambulance crew with what they believed to be a shotgun.
A man was taken to Royal Blackburn Infirmary at 10-30 a.m. on Wednesday for assessment, before being bailed without charge at Burnley Police Station later that day.
He will report back to the station on March 21st, when he will either be charged or released, said a police spokesman.
The police were alerted to the incident at 9-25 p.m. on Tuesday by the Lancashire Ambulance headquarters.
Mr Mike Abel, duty manager for the Lancashire Ambulance service, said: "It wasn't an emergency, it was a routine case given to us to take a man to hospital. When the crew arrived at the door the man presented himself with what appeared to be a shotgun. The two crew members made a tactical withdrawal and called the police."
Because of the remote location and being dark at the time, the police sealed off the property.
Mr Bob Parkinson, chairman of the joint unions in the ambulance service, said investigations were now in progress. We need to know what happened, why it happened, and why safety protocols were not sufficient to prevent it," he said.
Pasture Lane was closed off at both ends, as was the private lane up to Pasture House Farm, while police dealt with the incident at the farm belonging to Mr George Cox. On Wednesday morning, scores of cars and delivery vehicles were turned away from the lane, which leads towards Pendle's busy farming villages.
One couple who had taken their children to school were stopped at the bottom of their lane as they made their way back home, leaving the mother, who has her own catering business, concerned about food she had abandoned mid-preparation. The couple were allowed to return home within an hour when police agreed they were safe from harm.
The surrounding area remained closed off until just before midday on Wednesday, but a police car remained parked at the bottom of the lane leading to the farm.