A man initially charged with robbery and assault following an incident in Union City on Nov. 16 has now been charged with murder after the victim died.

Authorities say that Isaiah Grey, 23, assaulted and robbed 79-year-old Jorge Moctezuma Espinoza around 3 a.m. on Nov. 16 near 37th Street and Bergenline Avenue.

Espinoza died from his injuries on Nov. 22. The cause of death was determined to be blunt impact injuries to the head.

Grey is being held at the Hudson County Correctional Facility where he has been detained since the initial arrest on Nov. 16.