Kevin Esterly and Amy Yu have been missing since he withdrew $4,000 from his wife's bank account Monday

By Chris Harris
March 09, 2018 10:58 AM

Authorities are searching for a missing Pennsylvania teen and a 45-year-old married man who authorities say fled after investigators asked questions about what police allege was a “secretive” relationship.

A statement from the Allentown Police Department obtained by PEOPLE confirms Kevin Esterly and Amy Yu, a 16-year-old student at Lehigh Valley Academy Charter School in Hanover Township, have not been seen since Monday.

Yu and Esterly have both been reported missing and police think it is highly possible they are traveling together.

Police are looking for Esterly’s red 1999 Honda Accord with the Pennsylvania license plate KLT 0529.

Yu is an Asian female standing 4 feet 11 inches and weighing 90 pounds.

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Esterly, a white male, is 5 feet 9 inches tall and weighs 185 pounds.

A missing persons alert issued Wednesday by Allentown police listed both as possibly “endangered.”

The Morning Call obtained court records alleging a “secretive relationship” between the two.

Amy Yu and Kevin Esterly
Credit: Allentown Police Department

The paper reports that Esterly allegedly signed Yu out of the school 10 times between Nov. 13, 2017, and Feb. 9 — without her parents’ permission.

Yu’s mother, Miu Luu, learned her daughter had been signed out on Feb. 9 when she showed up at the school to pick the girl up. She called police that same day.

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A second call was made to authorities on Feb. 15. Police arrived at Yu’s home, and there, they found Esterly and his wife. The Morning Call reports the couple was warned to stay away from the girl’s home.

On Monday, Yu’s mother reported the girl as a runaway.

According to the Morning Call, police allegedly contacted Esterly’s wife, who said she last saw her husband Monday morning, and that he had withdrawn $4,000 from her bank account.

If seen or located, police ask people to call 911 or their local police department, or the Allentown Police Communications Center at (610) 437-7751 and report their location.