— -- Police are investigating the death of a 34-year-old woman this weekend after she allegedly received injections into her buttocks while in a basement of a home in Queens, New York.
Authorities are still looking for the person believed to have administered the injections, though police did not give any identifying information to ABC News and an arrest warrant has yet to be issued.
Kelly Mayhew was found unresponsive at the home in Queens on Saturday shortly after a 911 call was made by her mother, according to the New York City Police Department.
What was in the injections Mayhew had and how many she received was not immediately clear, police said, also noting that her initial autopsy was inconclusive. Investigators are unsure if the person believed to be responsible for administering the injections had a medical license or any training, a spokesman for the NYPD said.
The person believed responsible fled the scene after Mayhew started to have difficulty breathing, according to ABC's New York station WABC-TV. Mayhew's mother called 911 and performed CPR, WABC reported, but she could not be revived.
Mayhew was a Maryland-based freelancer for BET, according to WABC. The company later released a statement mourning her death.
"We are saddened by the death of our colleague and friend, Kelly Mayhew. Our hearts go out to her family, and we extend our deepest sympathies for their loss," the company said in its statement.
Illegal cosmetic procedures, including silicone injections, have been on the rise, said Dr. Scot Glasberg, president of the American Society of Plastic Surgeons.
He told ABC News earlier this year that common side effects of off-label injections can be scar tissue and infection if people do not use medical-grade silicone and instead utilize silicone more common in construction.
"If you walk into a garage or a basement or a dimly lit little room somewhere, your natural instinct should be to walk away, to run away," Glasberg said. "The downside of a little saving on cost is, potentially, your life."
Dr. Barney Kenet, a dermatologist based in New York City, explained that to legally administer cosmetic injections, a licensed physician or nurse or physician's assistant working in a doctor's office would need to use medical-grade materials from a licensed medical supplier. Additionally, the injections need to be administered in a medical setting that is appropriately sterile, has adequate lighting and the ability to access help for an emergency response.
There can be a number of issues with illegal injections, Kenet said, ranging from toxic materials to an embolism or heart attack.
But he noted that it would be impossible to know for sure what happened in Mayhew's case until final autopsy results came back.
"There was nothing about it that was safe. ... There was nothing about it that was ethical," Kenet said of the circumstances of this case. "This is so far outside the realm of medical care, this is criminal."
ABC News’ Sydney Lupkin contributed to this report.