POUGHKEEPSIE, N.Y. -- A high school English teacher is accused of violently stabbing a fellow teacher with a screwdriver on Thursday, sending her to the hospital and causing a brief lockdown at the school.

Police said Cynthia Glozier, 54, also an English teacher at Poughkeepsie High School, was stabbed as many as 18 times by Ronette Rocketts, 40, more than half of those in the back.

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School officials said the injured teacher was being treated at St. Francis Hospital and that police were investigating the fight.

The reason for the attack was unclear. The accused stabber is in custody; it was not clear if she had an attorney.

Officials locked down the school from about 10 a.m. to 11:15 a.m.

"No students were involved in the incident and no students were harmed," the school said in a statement.

After the lockdown, the school continued classes Thursday.

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