A man who was reported to be holding a gun and making threats towards a woman in Poole has been arrested.
Police were called to Belben Road shortly after 21:15 BST on Monday.
The 24-year-old was later arrested three miles (5km) away in Hastings Road on suspicion of possessing a firearm with intent to cause fear of violence.
Police said the firearm allegedly involved had not been found. Searches and house-to-house inquiries are being carried out.
The force said it was not known at this stage if the gun was real, imitation or an air weapon.
The man and woman were both known to each other and no-one was hurt, it added.
Det Insp Andy Bell said: "The public can expect an increased police presence in the area.
"I would ask anyone who comes across anything that resembles a firearm in the Canford Heath and Broadstone areas not to touch it, but to report it immediately to Dorset Police."