Ukraine Forces Move on Rebels in Kramatorsk

Ukrainian troops moved towards the rebel-held town of Kramatorsk on Saturday, with the government vowing it would not stop its operations to dislodge separatists. Russian media cited hospital sources as saying fighting overnight had killed one person wounded nine others.

The interior minister, Arsen Avakov, said troops had seized control of a television tower in Kramatorsk but gave no information on possible casualties, Al Jazeera reported.

"The active phase of the operation continued at dawn," Avakov wrote on his Facebook page. "We are not stopping."

Kramatorsk is near the rebel stronghold of Sloyansk, where rebels shot down two Ukrainian attack helicopters on Friday, killing two airmen and capturing a third.

That toll, however, was eclipsed by the deaths of dozens of people in a fire and street-fighting between pro and anti-Russian groups in Odessa, on Ukraine's Black Sea coast.

Regional police in Odessa put the death toll at 37, most of whom were killed when the trade union building in the city was set on fire. It said 200 people had been wounded. Local authorities had previously said 43 people had died.

The violence broke out on Friday afternoon, when the two sides confronted each other, to outnumbered police who were unable to control crowds throwing stones, bottles and stun grenades.

Later on Friday, a fire was started by unidentified men in the government building where separatists were sheltering.

Meanwhile, the US president Barack Obama and German chancellor Angela Merkel warned Russia it would face additional sanctions if Moscow disrupted Ukraine's plan to hold elections on May 25.