MOSCOW (REUTERS) - Russia shifted its stance over the bombing of a Ukrainian hospital in the city of Mariupol, with a mix of statements on Thursday (March 10) that veered between aggressive denials and a call by the Kremlin to establish clear facts.

Ukrainian President Volodymyr Zelensky said three people including a child had been killed in the bombing on Wednesday, and rejected Russian assertions there had been no patients there.

"Like always, they lie confidently," said Mr Zelensky, who has accused Moscow of waging genocide in the war it launched two weeks ago.

In the face of worldwide condemnation there were rare signs of inconsistency in the response from Russian officials, who since the start of Moscow's invasion on Feb 24 have stuck tightly to the same narrative for what Russia calls its special military operation in Ukraine.

Kremlin spokesman Dmitry Peskov, asked for comment in the immediate aftermath, told Reuters on Wednesday: "Russian forces do not fire on civilian targets."

On Thursday he said the Kremlin would look into the incident.

"We will definitely ask our military, because you and I don't have clear information about what happened there," Mr Peskov told reporters. "And the military are very likely to provide some information."

'Information terrorism'

Other Russian officials took a more aggressive line, rejecting the hospital bombing as fake news.

"This is information terrorism," foreign ministry spokeswoman Maria Zakharova said.

The Defence Ministry later denied having bombed the hospital, accusing Ukraine of staging the incident. It said Russian forces at the time had been respecting an agreement to hold fire to allow the evacuation of civilians.

"Russian aviation carried out absolutely no strikes on ground targets in the area," spokesman Igor Konashenkov said.

"The alleged air strike was completely a staged provocation... that can deceive the Western public but not an expert."

Foreign Minister Sergei Lavrov attacked what he called "pathetic shouting about so-called atrocities by the Russian armed forces".

He told reporters after meeting Ukraine's foreign minister in Turkey that the hospital building had for days been under the control of ultra-radical Ukrainian forces who had emptied out the doctors and patients - the version rejected by Mr Zelensky as a lie.

Moscow says it is conducting a special military operation to demilitarise and "denazify" Ukraine.

Kyiv and the West reject these as false pretexts for an invasion of a democratic country of 44 million people.

On Wednesday, the United States denied renewed Russian accusations that Washington was operating biowarfare labs in Ukraine, calling the claims "laughable".

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