A gunman opened fire at a Clifton church on Sunday, shooting three people in the head, and killing one.

Investigators say Joseph Pallipurath, 27, drove from California to New Jersey for his estranged wife, 24-year-old Reshma James, who was attending services at the St. Thomas Syrian Orthodox Knanaya Church on Third Street. According to police, the two argued in the church hallway before Palliupurath shot and killed James. He also shot Silvy Perincheril, a relative James was staying with, and 23-year-old Dennis John, who had tried to calm the fighting couple down. The shots were fired just before noon.

Multiple 911 calls were said to come from inside the church. Upon arriving at the scene, police locked down the church for almost two hours before releasing the emotionally distraught parishioners from inside.

The New Jersey State Police and county law enforcement agencies in northern New Jersey are assisting in the hunt for the shooter, who is of Indian descent, 5 feet 8 inches tall and 160 pounds. He was last scene driving a 2004 green Jeep Wrangler with a black soft top and California license plate 5JHD200.

The remaining two victims are in critical condition at St. Joseph's Medical Center in Paterson.

AP wire reports contributed to this article.