The UN said the latest reports from Ukraine show the need for "immediate de-escalation of the conflict."
The UN spokesperson said the organisation was not able to verify reports of Ukrainian shelling of Russian armoured convoy, which Ukraine said crossed border into Ukraine during the night.
Russia has denied that its troops entered its neighbour's territory.
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A woman hit by police gunfire during a counter-terrorism operation has been arrested after being released from hospital.
Police have been granted extra time to question a man who is being held on suspicion of planning a terror attack.
The man opened fire at the house, shattering the front door and window.