Officers in police vests and carrying rifles converged on the Humbert Street home off Park Avenue shortly after 9 a.m., a witness told Daily Voice.
Eastwick College and Washington Elementary School were subsequently placed on lockdown and area traffic diverted.
The woman was hospitalized with serious injuries while negotiators talked with the suspect, eventually convincing him to come out peacefully, Nutley Police Director Alphonse Petracco and Chief Thomas Strumolo said in a joint statement.
He was taken to a different hospital for undisclosed injuries, they said.
Petracco thanked Belleville firefighters for their assistance and commended his department's officers for their calm and professionalism. At no time was the public in harm's way, the director emphasized.
Strumolo said that police take precautions to protect civilians until a scene is determined safe.
He also said that an initial report among citizens that a gun had been used was erroneous. The injuries sustained by the couple weren't caused by a firearm, the chief said.
Click here to follow Daily Voice Mahwah-Ramsey and receive free news updates.