Ukraine has called an accusation its forces fired across the border "total nonsense".
Kiev suggested the attack, which is said to have killed one person, could have been the work of rebels trying to provoke Moscow to intervene on their behalf. The rebels denied they were responsible.
Inside Ukraine, combat has intensified dramatically since a rebel missile attack that killed dozens of government troops on Friday.
Local officials said on Sunday 18 people were killed in shooting incidents in the two main rebel-held cities.
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82-year-old Clayton Barnes arrived in the UK in 1959 as part of the Windrush generation, and worked and paid taxes for 51 years.
The American actor, best known for his portrayal of the character Mini-me in Austin Powers, has died at the age of 49.
A humid night for some with thundery downpours in places.