ELMWOOD PARK, N.J. (AP) -- Authorities are still trying to determine what caused more than a dozen students to become ill at a northern New Jersey school last week.

Elmwood Park school officials have said a glycol leak from an HVAC unit on the roof at the Gantner Avenue Elementary School may have caused the students and some staff members to faint or feel sick.

But speaking Tuesday night at a community meeting, they said a definitive answer hasn't been found. Hazmat teams have been at the school monitoring air quality, but no other dangers have been detected.

The school was evacuated Dec. 13 after a few students became sick. More students and some staffers became ill the next day, and the school was closed Friday for environmental and safety tests before it reopened Monday.

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