Live footage at the scene showed SWAT members set off some sort of explosive just before noon at an apartment on Columbia Drive in Finderne.
Moments later, members of the SWAT team escorted a woman out of the building and removed a man on a stretcher.
The woman was treated by paramedics while the man was loaded into an ambulance on a stretcher.
Circumstances around the incident weren't immediately clear.
Chief of Somerset County Detectives Frank Roman Jr. said only that one person was in custody and the investigation was ongoing.
"There is no threat to the public we expect to release further details later on this afternoon once the preliminary investigation is concluded and we charge the suspect involved in this incident," he concluded.
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