Armed police were called to a Hengoed street after reports of man possessing a firearm.
Officers were seen at Hawthorne Avenue from around 7pm on September 15.
A local resident, who wished to remain anonymous, said they saw between eight and 10 police vehicles in the area and said: "Everyone was told to [either] go indoors or leave the area.
"Armed police were present with guns and shields [It was] very unnerving considering the amount of police present."
A 49-year-old man, from Elliot's Town in New Tredegar, was arrested and remains in custody.
A spokesman for Gwent Police said: "We were called at 7.05pm on September 15 to a report of a man being in possession of a firearm (air weapon).
"Officers attended and arrested a 49-year-old man from Elliot's Town on suspicion of possession of a firearm with intent to cause fear of violence.
"He remains in police custody at this time."
