DUNCANVILLE, Texas (AP) — A Dallas-area school board has fired a teacher who posted racially charged tweets about the killing of a black 18-year-old by a white police officer in Missouri.

Duncanville Independent School District trustees unanimously voted Friday to terminate the contract of Vinita Hegwood (HEG’-wood).

The dismissal came a day after Hegwood, who is black, apologized for comments on her Twitter account that were laced with expletives and derogatory references to whites and blacks. Administrators called the remarks “reprehensible.”

Hegwood taught English at Duncanville High School. She’d been on unpaid leave and submitted her resignation Thursday, but the school board rejected it and instead fired her.

The tweets were related to Michael Brown, who was unarmed when fatally shot Aug. 9 in Ferguson, Missouri. The shooting has led to ongoing community unrest.