One of the girls remained in an emergency care unit on Friday, while the other one was hospitalized in less serious condition, said the Prosecutor General's Investigative Committee.
It said that before the girls were attacked, the officer sent an SMS-message to his common-law wife saying: "You may bid farewell to Dasha and Katya."
The fate of the two girls has generated widespread media attention and public criticism in Russia. Newspaper reports said the girls only survived because trees broke their fall from the apartment window and they landed on wet earth.
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