(Illustration by Park Ji-young/The Korea Herald) A woman has been arrested on suspicion of murdering her husband after allegedly putting a toxic substance into food they shared at a restaurant in what police believe was an attempted murder-suicide.Officials at Bundang Police Station said Thursday that the woman was formally arrested on June 22 over the death of her husband on May 20. Police believe she acted while under severe distress after their daughter’s death from cancer.According to police, the woman allegedly added a fatal chemical substance to the food the couple ate at a Chinese restaurant in Bundang-gu, Seongnam, Gyeonggi Province.The following morning, she was seen leaving their home while vomiting. Police and fire officials who arrived at the residence found her husband dead inside.Investigators found what appeared to be a suicide note, which suggested the woman had been depressed and felt guilt over her daughter’s death. Police said she had repeatedly told her husband that they should die together.The woman initially told police that her husband had agreed to die with her. However, surveillance footage from the restaurant showed her putting the substance into the food without his knowledge, and she later admitted that he had not consented, police said.Police declined to identify the substance involved. They said they sought an arrest warrant because they believed there was a risk she could attempt suicide again.* If you’re thinking about self-harm or suicide, contact the Ministry of Health and Welfare’s helpline at 109, available 24 hours a day, 7 days a week. Please request a translator for English-language services.