Police in Japan have arrested a woman accused of carrying out a chilling assault on her roommate by sewing the victim’s lips shut with a needle and thread, leaving the injured woman to flee into the street clutching a desperate handwritten plea for help.

The victim, a 42-year-old woman living in the eastern prefecture of Ibaraki, had reportedly been too terrified to escape immediately after the attack. Her roommate, identified by authorities as 49-year-old Masae Sakurai, allegedly stitched the woman’s lips together in a calculated act of violence inside the home they shared.

According to local reports, the victim waited until Sakurai left the residence before making her escape. She covered the lower half of her face with a white mask to conceal the injuries and hurried to a nearby shop. Unable to speak, she held up a handwritten sign that read “please help me,” prompting a shocked employee to contact police.

When officers arrived, the woman indicated that Sakurai had become enraged over some unspecified “trouble” between them and then attacked her, sewing her lips shut. Medical examinations cited in Japanese media described how a needle had been driven repeatedly through the skin, entering beneath the nose and exiting through the underside of the lower lip.

The thread was reportedly passed through the inside of the mouth, making the stitching difficult to detect at first glance and compounding the victim’s pain and fear. Authorities have not yet disclosed what was used to restrain the woman during the assault or how long she remained in that condition before escaping.

Sakurai was arrested on suspicion of assault. Investigators are still working to determine a precise motive and to clarify what dispute preceded the attack.

The case has stunned people who knew Sakurai. Acquaintances told Japanese broadcasters that she was known for taking in vulnerable young women, particularly those who had run away from home, and helping them find work. A former coworker described her as someone who “took care of girls who had nowhere to go after reaching out to their parents,” making the brutality of the alleged assault all the more disturbing.

The victim is receiving medical treatment and support as police continue their investigation into one of the most unsettling domestic violence cases to emerge from the region in recent memory.