(CNN) A New Jersey elementary school was placed on lockdown this week after a man was found in the parking lot with a gun and multiple rounds of ammunition, authorities said.

Officers found the suspect Thursday afternoon in the front seat of his SUV at Tamaques Elementary School in Westfield, according to the Union County prosecutor's office. He was holding a loaded .45-caliber handgun, it said in a statement Friday.

Classes had let out for the day, but the precautionary lockdown went into effect because after-school activities were still going on, CNN affiliate News12 reported.

The man, later identified as Thomas J. Wilkie, 46, of Bear, Delaware, had two additional loaded clips of ammunition on him and 130 more rounds in his vehicle's trunk, the prosecutor's office said.

Police acted on a tip from the New Castle police in Delaware that said Wilkie was on his way to the school and may be armed, according to the statement.

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