A Brooklyn public school teacher was arrested on Monday, and authorities say he was sexually abusing a student.

Daniel Santiago, a teacher at PS 244 in East Flatbush, was charged with first-degree sexual abuse and acting in a manner to injure a child under 17. Police say that Santiago groped an 11-year-old female student's genitals, chest, and buttocks on school grounds. The abuse allegedly began in February.

Santiago, 29, had been sending the girl "inappropriate text messages" and "someone spotted him touching the girl inappropriately," according to police sources. PIX 11 reports, "Word spread among the students, who then told another teacher at the school. The teacher told the principal, who then called police and made them aware of what was going on."

"This teacher was immediately reassigned away from the classroom when we were made aware of this disturbing allegation. We'll seek to remove him from payroll as quickly as possible while the investigation is pending," the Department of Education said in a statement.