Human remains have been found at the site where the last Tsar of Russia and his family were murdered in 1918.

It is thought that the bones - two skulls and a leg bone - could be those of Tsarevich Aleksei and Tsarevna Maria, two of Tsar Nicholas II's children, Russia's Ren TV reports.

It is difficult to say how such a grave happened to be here

Archaeologist Vladislav Svyatov

Their bodies were not among those buried in the mass grave after the Romanov family were executed by Bolsheviks, following the Russian Revolution the previous year.

Tsar Nicholas II, his wife Alexandra and three of his five children, Tatiana, Olga and Anastasia, were reburied in the imperial tomb in St Petersburg's St Peter and Paul Cathedral in 1998, along with their doctor and three of their servants.

But the bodies of the two other children have never been found.

Lost remains

The discovery was made by construction workers in Yekaterinburg, 20 metres from Ipatyev House - the spot where the Tsar's family were shot.

A Russian Orthodox church, the Saviour-of-the-Blood cathedral, is being built on the site.

A church marks the spot of the Romanov killings

The bones have been sent to a regional forensic laboratory and initial analysis suggests that the remains are of a woman and child.

This could fit the age profile of Tsarevna Maria and Tsarevich Aleksei.

Archaeologist Vladislav Svyatov told Ren TV: "A fragment of a leg, presumably a human leg, was found. It is possible that it may be related to the skulls, but maybe not.

"Before excavations have been conducted, it is impossible to say."

False alarm

A similar discovery was made two years ago during the excavation of Ipatyev House.

At the time, it was thought that the bodies might have been those of the Tsarevich and Tsarevna, but tests showed that the bones had been buried there before the killing of the Tsar's family.

"It is possible that this case will be similar. It is difficult to say how such a grave happened to be here. But the fact that somebody was buried here has been established," Vladislav Svyatov said.

Controversy

Scientists say the bones found in the mass grave are highly likely to be those of Tsar Nicholas II and his family, but their identities have not been conclusively established.

Archaeologists are studying the remains

The Patriarch of the Orthodox Church in Russia, Alexei II, disputed the authenticity of the findings and refused to officiate at the family's reburial ceremony.

Ren TV reports that the Yekaterinburg clergy have already informed Patriarch Alexei II of the latest discovery.

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