A Michigan woman who has been missing for over a month had been injured during an altercation over the summer, her sister said.

As CrimeOnline previously reported, Adrienne Quintal, 47, has not been seen since October 17, when she was staying alone at a family cabin in Honor, Michigan. In the early hours of the morning, Quintal called a friend and said she was in a shootout with two unknown men who were outside the home, and said she had shot one of them in the face.

By the time police arrived, delayed by an error in the reported address, Quintal was nowhere to be seen, but investigators found her boots and cell phone on the roof of the home. According to the Detroit Free Press, her gun, which she owned legally, was found on the ground; her purse was inside the home and her car was parked outside.

Quintal has not been seen or heard from since, and authorities have not located any sign of her in the woods near the cabin. Her sister Jenny Bryson told the Detroit Free Press that she is still trying to make sense of the disappearance.

“It’s a total mystery how she vanished,” Bryson told the newspaper.

The older sister revealed that Quintal had been “seriously hurt” in an altercation in July, and suffered a concussion. She did not provide details about the altercation, but reportedly said in an interview for a YouTube true crime program that she has considered the possibility her sister suffered some type of mental break as a result of the traumatic brain injury.

Authorities have not located the two men that Quintal said were at her home shortly before her disappearance.

MLive.com reports that Quintal’s family members are now offering a $100,000 reward for information about her disappearance.

Anyone with possible information about Quintal’s whereabouts is urged to call Benzie County Central Dispatch at 231-882-4487 or Michigan State Police Silent Observer at 1-866-774-2345.

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