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(FOX 9) - A registered sex offender is facing charges after he snuck onto a St. Paul school bus Thursday in Minneapolis, according to a letter sent to parents.
According to the letter from Chelsea Heights Elementary School, students took a field trip to the Walker Art Center on Feb. 28. During the ride home, "an unknown man was discovered sitting in the back of the school bus."
"When we were about halfway back to St. Paul, going down I-94, a man popped up on the back of the bus," said Maggie Zimmerman who was chaperoning her daughter's field trip. "One of our teachers saw him peek his head over and then go back down."
Video recordings showed that the man boarded after the driver exited the bus, prior to arriving at the Walker Art Center to pick up students. According to Zimmerman, he obtained entry onto the bus by prying the doors open with his hands.
The man was arrested once the bus arrived back at the school and all the students were back inside.
According to court records, the suspect is a registered sex offender. He was convicted of sexual contact with two 15-year-old boys. His criminal history also includes criminal sexual conduct convictions from 2011 and 2015.
"I googled him and the first thing that comes up is an article from 2011 about him boarding a school bus and masturbating in the back," said Zimmerman. "It's not an individual incident. It's a pattern. It's the thing that he does."
According to a letter sent to parents, at no time were students unsupervised by teachers and chaperones. No students were harmed during the incident.
Saint Paul Public Schools said in a statement it is conducting its own investigation to learn more about what happened and to strengthen bus safety procedures. SPPS has also informed its school bus contractors about the incident to reinforce required safety protocols. When a driver enters or exits a bus, they must walk through to verify that the bus is empty and ready for its next route.
Full statement from St. Paul Public Schools:
During a bus ride back to the school from a field trip in Minneapolis on Feb. 28, an unidentified adult was discovered sitting in the back of a school bus returning to Chelsea Heights Elementary.
The driver immediately called dispatch to alert police. Students were under direct supervision of school staff at all times.
The adult was taken into custody at the school without incident by the Saint Paul Police Department and they are investigating the individual.
Saint Paul Public Schools (SPPS) is conducting its own investigation to learn more about what happened and to strengthen our bus safety procedures. SPPS has also informed its school bus contractors about the incident to reinforce our required safety protocols.
The school is in regular communication with families affected by this situation.