Police say the letters have been sent sporadically over five years with the most recent coming within the last few weeks, CBS New York reported.
The letters are not just isolated to Dobbs Ferry. An employee at the Alcott Montessori School in Scarsdale has been a recipient of two of the letters. Authorities believe they are connected with the letters sent to Dobbs Ferry women, according to Patch.com.
Police are hoping to find DNA on one of the letters in an effort to catch the suspect, according to CBS New York.
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