A 23-year-old woman who was stabbed and killed on the light rail Friday night in South End has been identified as a Ukrainian refugee who recently fled Russia’s war on her home country. Iryna Zarutska was near East West Station, at East Boulevard and Camden Road, at around 10:30 pm, when police say a 34-year-old man stabbed her. Decarlos Brown, Jr., is charged with first-degree murder. Police haven’t said what led to the stabbing. According to a GoFundMe set up for Zarutska’s family, she had recently arrived in the U.S. to escape the war and start a new life.