There is a "high degree of probability" that bones found recently near the Russian city of Yekaterinburg are those of a daughter and son of the last czar, an official said Friday, citing preliminary forensic work.

If confirmed, the latest find would fill in a missing chapter in the story of the doomed Romanovs, who were killed after the violent 1917 Bolshevik Revolution ushered in more than 70 years of Communist Party rule.

The bones were found by archaeologists in a burned field near Yekaterinburg, a city in the Ural Mountains where Czar Nicholas II, his wife, Alexandra, and their five children were held prisoner by the Bolsheviks and then shot in 1918. The discovery was announced in August.