Police were called when a man allegedly threatened a bailiff with an axe in Barnstaple on Thursday afternoon.
The bailiff went to the industrial property in Castle Park Road at around 1.30pm when the man began wielding the axe, police said.
Police were then called and after 25 minutes a man left the building and gave himself up.
The bailiff was not injured.
Richard Bird, who works for Plumbase in Castle Park Road said he and his colleagues had seen very little.
"All we saw was the coppers pulling up and getting their gear on. The next thing you knew they were pulling him out of the unit."
Staff in the offices of Blue Sky said they had been unable to get a good look. One man said: "We saw what was going on but by the time we realised how serious it was and poked our heads out of the office door we were told to stay inside. I saw two armed police with whacking great guns, body armour and helmets. Obviously everyone stopped working and wondered what was going on."
Staff at Wilts Electrical said work had stopped for around 15 minutes when police first turned up.
And Jan Collins, from North Devon Hose and Hydraulics said the armed police had acted as if nothing out of the ordinary was going on.
He said: "We were outside talking to a customer when police turned up and told us to go inside. We stuck our heads out the door but were told to get back inside again. The armed police were just strolling across fairly casually. It wasn't as dramatic as in a film. But we said if they came crawling back on their belt buckles then we'd worry."
A police officer was seen leaving the scene with a metre long fire axe with a wooden handle, which was painted red at one end.
The man has been released on bail until December 20.