“Shelling from multiple rocket launchers on Sloviansk, the heaviest for a long time. There are 15 fires. Many dead and wounded,” Vadim Lyakh said in a video published on Facebook.
Tetyana Ignachenko, a spokeswoman for the Donetsk region to which Sloviansk belongs, told Ukrainian media that the strikes left “six dead and 15 wounded”.
She also reiterated a call on residents to leave the region, as the frontline is just a few kilometres (miles) away.
Ukrainian media said one of the city’s markets was on fire following the strikes.
Further south, the town of Kramatorsk, which is the administrative centre of Ukraine’s Donbas, was hit for the second day in a row by Smerch rockets, according to the town’s mayor Oleksandr Goncharenko.
The strikes, which hit a residential area and an unoccupied hotel, caused no casualties, he said.
Sloviansk and Kramatorsk are key targets for Moscow, particularly if the capture of Lysychansk in the northeast claimed by Russia on Sunday is confirmed.
