OAKLAND (CBS SF) — An act of retribution may have provoked a woman to brutally attack a third grader inside an Oakland elementary school bathroom, police say.

Students at Oakland’s Lafayette school knew something was wrong when they saw officers arrive at school Friday morning. They arrived to arrest Haseemah Diame, a parent and volunteer at the school.

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Police say Diame walked onto the campus during recess armed with a hammer and pulled a 9-year-old girl aside.

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“She was able to lure this other girl away from the play yard during recess into an adjacent bathroom there by the school. Once in the bathroom the adult proceeded to assault the girl with a hammer,” said school spokesman Troy Flint.

The attack was serious enough to draw blood.

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“It’s very horrible because I wouldn’t want that happening to my kid,” said Antoniette Badio, a parent at the school.

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A teacher and security guard found the girl injured in the bathroom with Diame and called police. Officials say the girl may have paid the price for a feud between her family and Diame’s.

The child was hospitalized with serious injuries, but is expected to recover. Diame is expected to face charges for assault with a deadly weapon.

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