ELIZABETH, N.J. — A 2-year-old is dead and two other pedestrians, including another child, are hurt after they were struck by a postal truck in New Jersey, authorities said.

The crash happened Monday on Rahway Avenue near South Street and Chilton Street.

The children's grandmother was walking with the toddler and a 4-year-old when the collision occurred, officials said.

No names have been released. The grandmother, who is in her 50s, underwent brain surgery after the crash. The 4-year-old boy was taken there, as well, with a few abrasions, waiting to be picked up by his father.

The sheriff’s office and police department are working together as the crash is still under investigation.

Witness Andres Figueroa told PIX11 News the woman was carrying the youngest victim in her arms when the truck came toward them. She turned back to the truck, apparently in an attempt to protect the toddler, but when she was hit, the child went flying out of her arms and landed on the pavement.

Figueroa said that child and the woman lay motionless on the ground, while the second child ran back across the street. A bystander grabbed that child and held them in her arms until police arrived, Figueroa said.

The driver of the mail truck was unharmed and is cooperating with investigators, some of whom from the postal service were on scene interviewing witnesses midday Monday.