FALLSBURG - Benjamin Cosor Elementary School officials say a security firm has been hired to monitor the school following the recent discoveries of heroin in the building.

The school superintendent says the extra security measure will begin on Monday.

The field of suspects was narrowed to seven teachers caught on surveillance cameras that were installed after empty heroin bags and hypodermic needles were first discovered in a restroom back in December. Those seven teachers refused to be drug-tested and remain in the classroom while under police investigation. 

School Superintendent Ivan Katz said that the teachers have not been suspended because of their contracts.

On Wednesday night, about 150 parents attended a school board meeting to voice their outrage. Former PTA President Andrea Hook says she's petitioning lawmakers to make drug-testing of teachers mandatory in New York.