Police were called to the state-operated facility for troubled youths at 1075 Broadway at 12:07 a.m. Thursday.
A 17-year-old boy was slashed with a box cutter on the forehead and on the left side of his neck, under his ear, Mount Pleasant police said.
The boy was taken to an area hospital where he was treated and released after receiving stitches, police said.
Lt. Robert Miliambro, a spokesman for the Mount Pleasant Police Department, said the names of the youths charged, who are 17 and 19, were not released because they may qualify for youthful offender status.
They were due to appear in Mount Pleasant Town Court on Thursday.
Mount Pleasant police called for backup assistance from Pleasantville and Westchester County Police departments to prevent the fight from escalating, according to Miliambro.
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