The incident happened while officers were responding to a call at a home on Hannah Drive, near Marc Drive, in South Brunswick around 10:30 p.m Wednesday.
Authorities say 28-year-old Andrew Murnieks was fatally shot inside his residence by a police officer who is part of the county special operations team.
Members of the South Brunswick Police Department were dispatched to the residence about 6:30 p.m. on a report of an emotionally disturbed person. Upon arrival, Murnieks' mother told officers that her son was schizophrenic and had not been taking his medications.
Township police had responded to prior incidents at the house involving Andrew Murnieks.
As South Brunswick officers approached the house, police say Murnieks opened the front door and raised a large knife above his head in a threatening manner. The officers shut the door, retreated and alerted the County Special Operations Response Team.
A crisis negotiator made repeated efforts over the next several hours to resolve the situation. When those efforts failed, members of the county team entered the residence about 10:30 p.m.
Inside, police say Murnieks assaulted a police officer, who fired a single shot from his service weapon, striking Murnieks in the chest.
He was treated at the scene by paramedics and rushed to Robert Wood Johnson University Hospital in New Brunswick, where he was produced dead at 11:35 p.m.
The incident remains under investigation.