The report prompted parts of Route 119 to be closed at police and firefighters responded to 247 Tarrytown Road. The Westchester Bomb Squad also responded.
Traffic on Tarrytown Road in front of the location was diverted in both directions.
After the grenade was determined to be inert -- and harmless -- the area was deemed safe and opened for all traffic at 12:45 p.m., police said.
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