Human Interest Loved Ones Discover Missing Arizona Sisters Died by Assisted Suicide on European Vacation Lila Ammouri and Susan Frazier were expected to return home from a trip to Europe in February, but it wasn't until weeks later that people discovered the sisters died from assisted suicide By Jason Hahn Jason Hahn Jason Hahn is a Human Interest and Sports Reporter for PEOPLE. He's worked at PEOPLE's Los Angeles Bureau as a writer and reporter since 2017 and has interviewed the likes of Kobe Bryant, Arnold Schwarzenegger and Tom Brady. He has a B.A. in English from the University of California, Berkeley, and a Master's degree in Journalism from Columbia University. He previously worked for Complex Magazine in New York City. People Editorial Guidelines Published on March 29, 2022 04:50 PM Share Tweet Pin Email Trending Videos Two Arizona sisters died by assisted suicide while visiting Europe in February, according to the clinic that assisted them — and now loved ones say they had no idea the siblings were planning to end their lives. The sisters, identified as Dr. Lila Ammouri and Susan Frazier, flew from the U.S. to Zurich, Switzerland, on Feb. 5, Phoenix FOX affiliate KSAZ reported. Both Ammouri, a 54-year-old palliative medicine specialist, and Fraizer, a 49-year-old registered nurse, were scheduled to return from their trip about a week later but never arrived, according to the outlet. Dr. David Biglari, a friend of the sisters, told the news station the pair were "in a very good position of their lives in terms of careers," and he knew of no reason they wouldn't return home on their own. "I'm totally devastated and don't have a clue why they did this," Cal Ammouri, identified as the sisters' brother, told the New York Post. "We still need answers," Biglari told the newspaper. People who knew Ammouri and Frazier were concerned foul play was involved in their disappearance after they received a questionable message on Feb. 10, Biglari told KSAZ. "Some of the text communications they had, we are certain they were not from them," Biglari said. "They were most likely fabricated with someone else." However, amid the search for the duo, assisted dying nonprofit Pegasos announced on Sunday that the sisters died by assisted suicide at their clinic in Liestal, Switzerland on Feb. 11. Warning Signs to Look for If You Are Concerned Someone Is Suicidal "Although they had a number of health problems, they were not terminally ill," Pegasos said in the statement, which was published jointly with Exit International, an organization that advocates for the legalization of voluntary euthanasia. "They expressed a strong wish to die together." The organizations claimed the sisters researched other ways to die by suicide but visited the Pegasos clinic due to their fear of "possible failure." "They also realised that their desire to die together, when not terminally ill, could not be accommodated by any of the right to die legislative changes introduced into a number of US states," the statement said, adding that the sisters were medically reviewed in Switzerland and their mental capacity was assessed by independent professionals. The deaths were also confirmed by the United States Department of State, KSAZ first reported. "We can confirm the death of two U.S. citizens in Switzerland," a State Department official says in a statement to PEOPLE. "Out of respect for the privacy of the family, we have no further comment at this time." RELATED VIDEO: Dad Helps Women with Postpartum Depression After His Wife's Death by Suicide: 'It's My Therapy' Ten states in the U.S. — California, Colorado, Hawaii, Maine, Montana, New Jersey, New Mexico, Oregon, Vermont and Washington — as well as the District of Columbia permit doctor-assisted suicide for mentally healthy patients who have no more than six months to live. In March, novelist Amy Bloom opened up to PEOPLE about her late husband, architect Brian Ameche, who chose to die by assisted suicide in Switzerland in 2020 after learning he had Alzheimer's disease in 2019. "He knew what he wanted. He wanted to control his death and he wanted my support," Bloom said of their "excruciating" journey. Novelist Amy Bloom Shares 'Excruciating' Journey After Her Ailing Husband Chose to Die By Assisted Suicide The topic came under national attention in 2014 when Oregon resident Brittany Maynard spent the final months of her life advocating for assisted suicide laws before ending her own life at age 29 during a battle with brain cancer. Assisted suicide in Switzerland has been legal since 1942, according to Dignity in Dying, a British organization. If you or someone you know is considering suicide, please contact the National Suicide Prevention Lifeline at 1-800-273-TALK (8255), text "STRENGTH" to the Crisis Text Line at 741-741 or go to suicidepreventionlifeline.org.