A woman entered the school and swiped a timecard from a record-keeping machine at the school between 7:45 and 7:50 a.m., Police Sgt. Simon Blanc said.
An intern at the school didn't recognize the woman, whom she thought might be a substitute teacher, approached and spoke with her, Blanc said.
The woman didn't answer, he said, instead saying she forgot something in her vehicle and returned to the parking lot.
Thinking quickly, the intern followed the woman and snapped a photograph of the license plate of the small white car as the woman drove away, he said. The vehicle is owned by a Norwalk resident, police said.
However, when police checked the name of the vehicle's registered owner, school officials said that person was not a public school employee, Blanc said.
Police are investigating.
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