A popular teacher in the Valhalla Central School District was arrested on drug charges.

Greenburgh police say Gjon Krasnici was arrested Friday and charged with criminal possession of a controlled substance. There is no word yet on what that substance is, and so far, there have been no further details about the arrest.

Krasnici has been teaching kindergarten through second grade at the Virginia Road Elementary School for more than a decade.

"I'm surprised because the teacher was good, got along with all the kids, like a father to the kids, really good," says parent Santo Rivera.

Parents received a letter over the weekend from district officials that read in part, "This is a difficult situation for our school district, and we will work together to ensure our students...staff and families are supported during the transition."

Many parents tell News 12 they were shocked when they received the email this weekend.

The school district is in the process of making arrangements for Krasnici's students for the rest of the school year.