DHAKA: East Ukraine is braced for more unrest, as troops from Kiev prepare to continue "anti-terror" operations and pro-Russian gunmen reinforce barricades.

Ukrainian soldiers advanced on several cities on Saturday to regain control of buildings seized by the gunmen, reports the BBC.

But in at least one city, Luhansk, the rebels made further gains, storming a security services base.

Clashes in the southern city of Odessa in which at least 42 people died in a fire have further raised tensions.

Pro-Russian protesters had gathered at Odessa's Trade Unions House after running battles with pro-Kiev activists.

The building caught fire, killing many of the protesters.

A Russian government spokesman accused Ukraine's government of encouraging nationalist extremists and said it would be "absurd" for the country to hold a planned presidential election on 25 May.

The violence in Odessa was the most serious in Ukraine since February when more than 80 people were killed during protests in Kiev against the ousted President Viktor Yanukovych.

The blackened trade union building was ringed by police on Saturday and there were some scuffles as groups chanting pro-Russian slogans clashed with government supporters.

BDST: 1056 HRS, MAY 04, 2014