TAMPA, Fla. (WFLA) — A Florida medical examiner has released information on what exactly caused the death of Mary Jane Thomas, the late wife of country music singer Hank Williams Jr.

A report obtained by WPTV said Thomas died of a collapsed lung, which was punctured during a cosmetic procedure on March 21. The 58-year-old died the day after the procedure, according to reports.

The autopsy report from the Palm County Beach medical examiner, which was signed on Friday, said the death was accidental.

According to WPTV, Thomas was undergoing a breast reduction and liposuction at Bafitis Plastic Surgery in Jupiter, Fla.

Jupiter police said in the report that Thomas was behaving and speaking normally while she recovered at the Jupiter Beach Resort & Spa when she “became unresponsive.”

She was rushed to the Jupiter Medical Center’s emergency room, where she died.