A Philadelphia woman, Antoinette Pelzer, 44, was arrested at the scene, The Press of Atlantic City reported. She was charged with aggravated assault and robbery, Atlantic County Prosecutor Ted Housel said, and murder charges were expected to be added after her alleged victims died.
"This was a random and bizarre act of violence," said Tom Gilbert, police commander of the gambling resort's Tourism District.
Officer Jacob Abbruscato, who was in a police cruiser, witnessed the attack in an area half a block from AtlantiCare Regional Medical Center and next to Bally's Atlantic City Bus Center. Pelzer complied with Abbruscato's order to drop her weapon, police said.
The victims' identities were not released because their families had not yet been notified of their deaths, police said. One was 47 and the other 80.
Nativity scenes to be moved at Guantanamo after troops' protest
2013: Top 11 Bacon stories of the year!