A series of explosions have been heard in rebel-held Donetsk region for the second day running.
Multiple explosions were heard in the centre of the separatist-controlled city late on Saturday and into the early hours of Sunday morning, following similar blasts on Saturday morning.
It was not clear what caused the explosions, and there was no immediate comment from separatists or Ukrainian authorities.
But it comes after reports emerged of almost 2,000 ceasefire violations in eastern Ukraine on Friday.
Footage and images have emerged online and in the media of the violence in eastern Ukraine, which has housed conflicts between Ukrainian government and separatist forces since 2014.
Several instances of shelling in Donetsk and neighbouring Luhansk - now a hotbed for tensions between Russia and the West - have been registered by monitoring authorities.
A bomb struck a car outside an official building in Donetsk on Friday, succeeded by two explosions in Luhansk early on Saturday.
The Luhansk Information Centre said one of the blasts was in a natural gas main and cited witnesses as saying the other was at a vehicle service station.
A mass evacuation of women, children and the elderly from the rebel-held territories to neighbouring Russia has been launched.
Head of state of the Donetsk People’s Republic, Denis Vladimirovich Pushilin, said they were being moved to safety to avoid shelling by Ukrainian forces.
It comes after monitors for the Organisation for Security and Cooperation in Europe (OSCE) logged 1,400 explosions and one civilian casualty in the regions of Donetsk and Luhansk on Friday.
Meanwhile Boris Johnson today warned that “all the signs” are there that Russia has commenced plans to invade Ukraine.
Speaking to the BBC’s Sunday Morning programme, Mr Johnson said: “I’m afraid that is what the evidence points to, and there is no burnishing it, no hiding it.
“The fact is that all the signs are that the plan has already in some senses begun.
“That’s what our American friends think and you’re seeing these provocations now in Donbas - these explosions and so on - that we’ve been warning about for a long time.”
He went on to add that that Kremlin chief Vladimir Putin might not be thinking logically, and therefore any threat of sanctions on Russia by the West might not be enough to deter an invasion of Ukraine.
He said: “We have to accept at the moment that Vladimir Putin is possibly thinking illogically about this.”
Sanctions “may not be enough to deter an irrational actor and we have to accept at the moment that Vladimir Putin is possibly thinking illogically about this and doesn’t see the disaster ahead,” Mr Johnson told the broadcaster.
He added that said he was unable to “peer into the soul” of Mr Putin, and therefore couldn’t say when an or if an invasion of Ukraine might happen.
