Mississippi state Rep. Jessica Upshaw was found dead of a gunshot wound Sunday afternoon, and it appears that she may have killed herself, though the official report on her death has not yet been released.

The Republican legislator, 53, was found by law enforcement authorities in a house in Mendenhall, Simpson County Sheriff Kenneth Lewis told Mississippi's WLBT news station, adding that it seems that she had fired the bullet that took her life.

"It appeared she had a gunshot wound to her head; it appeared to be self-inflicted," Lewis said Sunday. "Her body was found at 901 Mangum Street ... We arrived on the scene around 2 p.m. this afternoon. We usually assist Mendenhall P.D."

But Lewis told WLBT that authorities are waiting on the State Crime Lab to release a report determining Upshaw's official cause of death.

And ABC News reported Monday afternoon that no arrests have been made in the case. CBS News reports that Upshaw's death marks the fifth Mississippi state legislator to die in the past five months, but the other four succumbed to natural causes.

The legislator represented the Mississippi House of Representatives' District 95 -- which includes Hancock and Harrison counties -- since 2004, according to the Jackson Clarion-Ledger, which is based in the state capital.

The home in which Upshaw was found is apparently the residence of Republican former state Rep. Clint Rotenberry, according to the Clarion-Ledger.

Simpson County Coroner Terry Tutor declined to provide specifics regarding Upshaw's passing to the newspaper, saying only that, “She’s passed; that’s all I know at this point ... I’ve given it to MBI. They’re doing their investigation on it.” 

Warren Strain, a spokesman for the Mississippi Bureau of Investigation, also spoke with the Clarion-Ledger about Upshaw's death.

“The crime scene unit is processing the residence, and the investigators are conducting interviews and following leads. It would be premature to make any statement regarding the investigation at this point," Strain said.

Mississippi Gov. Phil Bryant issued a short statement about Upshaw's death on his official website on Sunday.

“Deborah [his wife] and I were saddened to hear of the passing of Rep. Jessica Upshaw. I have known Jessica for many years as an unselfish and dedicated public servant. This is a tragic loss for her family and all Mississippians, and our thoughts and prayers go out to her family during this difficult time."

House Speaker Philip Gunn also expressed his condolences on the death of Upshaw, who had degrees from the University of Mississippi and Ole Miss Law School, according to the Clarion-Ledger.

“Once again this session, the House has been touched by tragedy," Gunn said in a statement. "Representative Jessica Upshaw was an outstanding legislator and friend. She was one of the brightest and most competent members of the House. Our hearts break for her family, and our prayers go out to them during this tragic time.”

Upshaw was an unmarried former attorney who served as chairwoman of the House Conservation and Natural Resources Committee, according to NBC News.