Several students and staff escaped unharmed when a fire broke out at a private northern New Jersey school that serves children with special needs.

Classes at the Center School in Highland Park had ended before the fire broke out around 5:30 p.m. Tuesday. But roughly 18 students and nine adults were still in the three-story brick building at the time, taking part in after-school activities.

Firefighters from Highland Park and other nearby communities were able to quickly bring the blaze under control. But school officials say no classes will be held Wednesday due damage caused by the fire.

The caus e of the fire remains under investigation.

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