POLICE called to reports of an assault at a farm in East Bierley found a cache of weapons dating back to the Second World War.
Among the items were two live hand grenades and officers drafted in help from army bomb disposal experts who blew them up in a controlled explosion.
Homes surrounding Model Farm in Toftshaw Lane were evacuated and a police cordon was set up around the scene.
Police were initially called to the farm at 5.30am on Tuesday following reports of an assault on a man in his 60s, but when they searched the farm and outbuildings they found more than 20 antique guns.
The site also includes a farm shop and a bed and breakfast but the two hand grenades were found in the main building. The farm is on the outskirts of East Bierley, near the Princes Soft Drinks factory.
Eighteen residents were told to leave their homes as the army officers dug a small trench in which to safely explode the grenades.
The cordon around the farm was kept in place until late on Tuesday, but the bomb disposal team returned on Wednesday to continue searching the farm buildings.
The owner of the farm has been named locally as Allan Bamford, 62, who lives there with his son Richard, 36, and the pair run the businesses between them.
One resident of Toftshaw Lane, who did not want to be named, said: “The police knocked on my door and told us we had to leave our house.
“Then bomb disposal teams and Army officers turned up and there was a very loud bang. There was a steady flow of police officers turning up as well.
“I’ve heard that the owner collects army memorabilia. They have all sorts of things like old cars, fire engines and an old locomotive.”
Police have confirmed that there was no danger to residents during the operation.
Bradford South Acting Supt Mark McManus said: “The initial searches uncovered a number of de-commissioned military memorabilia, however two live grenades were also located and a controlled explosion took place to make these safe. There was no immediate threat to residents and we continued our searches into the evening to ensure no further devices were on the site.”
A 36-year-old man was arrested in connection with the alleged assault but was then questioned by detectives about the weapons. He has been released on bail pending further enquiries. It is not known whether he knew the grenades were still live.