MIAMI — A South Florida woman posing as a doctor was arrested today and charged in the death of a woman who died after authorities said her body was pumped with unknown toxic substances during a buttocks-enhancement surgery.

Shatarka Nuby, a 31-year-old mother, paid a woman known as “Dutchess” hundreds of dollars to come to her house and inject her buttocks, hips, thighs and breasts with an unknown substance. Dutchess, whose real name is Oneal Morris, sometimes wore medical scrubs and a stethoscope. Morris — who police say was born a man and identifies as a woman — allegedly sealed Nuby’s injections with super glue and cotton balls, according to Broward County Sheriff’s deputies.

Nuby told friends the injections became hard and hot and that her skin turned black. She wrote a letter to Department of Health investigators before her death in March in Tallahassee. An assistant medical examiner said she suffered “massive systemic silicone migration” from the injections, according to a release from the sheriff’s office.

Authorities said Nuby was one of several victims who sought out 32-year-old Morris for cosmetic procedures. Some of the victims developed complications and infections after the injections, which included bathroom caulk, cement, Super Glue, Fix-A-Flat and mineral oil into the bodies of her victims, deputies said.

Morris was arrested at her mother’s South Florida home today and charged with manslaughter. Her attorney, Michael Mirer, declined comment.

Morris also was arrested last fall after nearly a year of being sought and charged with practicing medicine without a license with serious bodily injury. Authorities said a victim who was looking to get a job at a nightclub and wanted a curvier figure paid Morris $700 for the injections in 2010. Morris allegedly used some type of tubing and inserted the toxic chemicals into her backside during a painful procedure.