Kazakhstan has confirmed that two teenagers killed in the U.S. state of Washington last week in a multiple slaying were adopted as children from Kazakhstan.
The Education and Science Ministry said on February 29 that the two boys -- Timur Tory Carlson, 18, and Damir Quinn Carlson, 16 -- were from Kazakhstan's northern region of Aqmola and were adopted in 2002.
The boys, originally named Timur Daniyarovich Koktiev and Damir Dulatovich Abdrakhmanov, were adopted from an orphanage in the city of Shchuchinsk.
The authorities in Astana are still trying to determine whether the two retained their Kazakh citizenship or had become naturalized U.S. citizens. But Kazakhstan's human rights ombudsman's office said the case needed to be thoroughly analyzed "in order to prevent similar tragedies from happening to our fellow citizens in the future."
The two teenagers were among four people shot by 51-year-old David Wayne Campbell on February 25 at his rural home near the town of Belfair, Washington.
Campbell also killed his 49-year-old wife, Lana Carlson, who reportedly adopted the two boys during a previous marriage, and another victim, a female neighbor. Campbell committed suicide by shooting himself in the head during an ensuing standoff with police.
Earlier reports said that the boys had been adopted in Russia, which controversially banned Americans from adopting Russian children in 2012 in what was seen as retaliation for economic sanctions.
Russia's ombudsman for children's rights, Pavel Astakhov, said on February 28 that it was difficult to determine the boys' citizenships due to "Washington's rejection of Moscow's proposal to establish a unified system to register all children adopted abroad."