Henry Werner, 61, now faces a murder charge. He was arrested Monday morning by an off-duty police officer at the Richfield Shopping Center in Clifton.
Debbie Roon, who works in a laundromat in the shopping center, said Werner was known there as Hank.
"In the five years I've been here, we've never had a problem with Hank," she told WNBC-TV. "He's been very respectful."
Passaic County Prosecutor Camelia Valdes said that just before 7:30 a.m. Werner stabbed Paul Baker, 67, of Clifton and then attacked Clarence Wispelwey, 80, who tried to intervene. Baker died, while Wispelwey was reported to be in stable condition at St. Joseph's Hospital and Medical Center in Paterson.
Werner faces charges of murder, attempted murder and possessing a knife. He was arrested by David Strus, a police officer in nearby Nutley.
Valdes said investigators do not know why Werner decided to attack Baker. Baker and Wispelwey were walking across the parking lot at the time.