(CNN) A 10-year-old Muslim girl found two threatening handwritten notes in her cubby in an elementary school west of Boston, and police are investigating the notes as a hate crime.

The first note came on Friday. Scrawled in pencil was: "You're a terrorist."

On Tuesday, the student found a second threatening note: "I will kill you."

Neither the fifth-grader who received the notes nor the other students at the school are thought to be in imminent danger, Framingham School District Superintendent Robert Tremblay said in a news conference on Wednesday. "Safety is our priority," he said.

In addition to the police investigation, the school district is conducting a separate internal investigation, Tremblay said.

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