UPDATED: More than 20 police officers attended a Berrimah trucking company Friday morning, searching the grounds for a gun that was allegedly used by an employee who threatened his employer in a three-hour standoff with police overnight, NT Police have confirmed.

Reports and photos from the scene Friday morning showed more than 20 officers, including members of the Territory Response Group, were on the premises of NT Hauliers on 14 Pruen Road.

It is now understood they were searching for a gun which they retrieved.

NT Police said they arrested a 50-year-old man on Thursday night after he allegedly threatened his employer with a firearm at the site that turned into a three-hour armed stand-off with negotiators called in.

“Police attended the business in Pruen Road and cordoned off the area as a precaution around 6pm [Thursday night],” said Detective Acting Senior Sergeant Andrew Kren.

“Negotiators engaged with the offender, who was taken into custody around 9pm. He was not in possession of a firearm at the time of his arrest and nobody was injured.”

NT Hauliers says on its website that it is a local Territory-owned transport and logistics company that provides services throughout the NT, as well as linehaul services to North Queensland, South Australia and Victoria.

Calls to the company’s office went unanswered Friday.

NT Police said investigations are continuing and detectives in the Serious Crime Unit are expected to lay charges later this evening.