The student's father tells WCMH-TV (http://bit.ly/2e3OSiV ) that his 7-year-old daughter reported that the male teacher made the threat on Wednesday in Newark.
The girl's father, Denver Ham, says there's no room for making such comments even as jokes, given the prevalence of real school violence.
Newark City Schools says in a statement that the teacher's reported comments are alarming and unacceptable. The district is apologizing to affected students and their parents.
The district says the guest teacher won't work in Newark schools pending the results of an investigation. The statement didn't name the teacher.
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