A first grade student from Hackensack, Bergen County, New Jersey died Thursday after suffering from an E. coli infection.

Health officials are investigating the source of the child’s illness, but have yet to find the source.  Jackson Avenue School sent a letter home to parents, alerting them of the child’s illness and death, and notifying parents that health officials had not found reason to believe the child contracted E. coli at school.

"We are very confident at this point based on the information they provided us that this is an isolated incident and there is no need for concern," Hackensack Superintendent Dr. Joseph Montesano told CBS 2 HD.