A group of high school girls have yet to be diagnosed after coming down with a mysterious illness two months ago, 13WHAM News reported.

An estimated 12 students at LeRoy High School in Leroy, N.Y., started suffering in November from shaking, tics and vocal outbursts similar to those of Tourette’s syndrome.

"The investigation has not revealed environmental or infectious causes as the origin of the students' illness," said Jeffrey Hammond, spokesman for the New York State Department of Health.

The school district hosted a public meeting Wednesday to update hundreds of concerned parents about the health investigation, but were unable to give any information because of federal privacy laws.

The district’s website posted the following comment:

"The safety and well-being of all students and school staff is our top priority. The District continues to work with medical specialists, the State and County Health Departments, and the County and State Office of Mental Health during this ongoing investigation."

Residents have expressed frustration with the lack of information given up to this point.

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