NEW YORK (CBSNewYork) -- A school shooting threat made over social media has prompted police to beef up security at three high schools in Brooklyn.
The threats involve Edward R. Murrow High School, at 1600 Avenue L in Midwood; James Madison High School, at 3787 Bedford Ave. in Marine Park; and Midwood High School, at 2839 Bedford Ave. in Flatbush.
Edward R. Murrow High School sent a robocall to parents notifying them about a series of threatening posts, including a tweet.
The acting principal said: "All appropriate actions have been taken to ensure your child's safety. We will do everything to ensure your child's safety."
There was no police activity outside James Madison High School Thursday night.
Parents contacted police about the postings Thursday.
Investigators believe the threats themselves are old and were recently reposted to social media.
Although the NYPD does not think the threats are credible, it has increased security as a precaution.
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