"There are no documents – Russian birth certificates, passports or Russian adoption papers – linking them to Russia. But that cannot be ruled out," the unnamed official said.
Earlier, officials conducted a second search of a property in Mason County southwest of Seattle, where a man fatally shot four of his family members and committed suicide in front of police.
David Wayne Campbell, 51, was said to have shot and killed his wife, two children and an unidentified person before turning the gun on himself. The county coroner identified three victims: Lana J. Carlson, 49; Quinn Carlson, 16; and Tory Carlson, 18.
A 12-year-old girl believed to be related to the victims was found at the site unhurt.
The identity of a fourth victim has not been released until notification of next-of-kin.
Local media reports cited preliminary information alleging that the two teenagers may have been adopted in Russia. Later unconfirmed reports claimed the teenagers may have been born in Kazakhstan.
The Russian Consulate General official said the search was likely to continue for a considerable time due to the property’s vast size.
