On July 17, 1918, Tsar Nicholas II of Russia, his wife, and his five children were woken up before dawn, led into a basement, and shot by a firing squad. Their bodies were burned, doused in acid, and later dumped into a mass grave near the Ural Mountains.

In 1991, construction workers uncovered the corpses, and scientists later confirmed, via genetic testing, that they belonged to the Romanov clan. The family was eventually canonized and buried in St. Petersburg’s Peter and Paul Cathedral. However, two skeletons remained missing—the bones of Crown Prince Tsarevich Alexei and the Grand Duchess Maria. For years, rumors swirled that the two had somehow survived and fled Russia.  

In 2007, researchers confirmed that the two children’s bodies had finally been found in another grave nearby. After years of delays, a high-level government task force has been planning to bury the two alongside their family at the cathedral this fall. However, the Russian Orthodox Church still questions the authenticity of the remains, and now wants to conduct further testing before declaring the new skeletons holy relics.

To assuage all doubts, Russia’s investigative committee re-opened the case of the family’s murder. Earlier this week, they exhumed the remains of Nicholas II and Empress Alexandra Fyodorovna, according to the AFP. The committee also collected other pieces of evidence, including samples from the bloodstained uniform of Nicholas II’s grandfather, Emperor Alexander II, who died in a bombing in 1881.

As for now, the bones of the Crown Prince and the Grand Duchess are being held in the Russian State Archives, where they’ve lain since 2007. It looks like they’ll sit there a little longer until the Church is satisfied they officially belong in the Romanov family crypt.

[h/t The Guardian