KIEV, Nov. 28 – Ukrainian opposition parties on Monday demanded an immediate investigation into a crackdown on a street protest in Donetsk as a result of which one person died.

Arseniy Yatseniuk, the leader of the Front for Changes party, said Prime Minister Mykola Azarov must be summoned to an emergency session of Parliament to report on the issue.

“The parliamentary opposition has submitted a draft resolution to create the investigative committee,” Yatseniuk said in an interview with Channel 5. The committee will investigate the “terrible case when the person has been simply killed.”

The developments come a day after one of about 30 protesters who had been on hunger strike in Donetsk over pension cuts died Sunday night after police broke up their tent encampment.

Gennady Konoplyov, 70, was taken ill and died in an ambulance after the police operation, after joining the protest of Chernobyl clean up workers.

Meanwhile, the protest expanded on Monday with a group of 100 retirees, armed with pitchforks and shovels, attacking an office of the Donetsk regional administration, local media reported.

The protesters demanded a meeting with Donetsk governor Andriy Shyshatskiy, who had refused to meet the protesters.

The escalation of tensions comes as the government has been seeking to cut social benefit payments to millions of Ukrainians, citing shortage of funds in the budget.

“We see how fast the level of aggression is rising in the society,” the opposition UDAR party, led by Vitaliy Klichko, said in a statement. “What’s important is that the protest has taken place in a region whose population has been most supporting the governing party.”

The developments are a personal embarrassment for President Viktor Yanukovych. Donetsk is his home town and normally a loyal bastion of support for him and his Regions Party.

Reform of Ukraine’s bloated pensions system is one of the commitments that Yanukovych's government has had to make to the International Monetary Fund in return for a $15 billion stand-by program.

It is dragging its heels, however, on another promise to the IMF to raise the price of household gas which it fears will dent the popularity of the Regions Party before a parliamentary election next October.

The Chernobyl disaster-fighters, who were evacuated with their families from the northern region 25 years ago, have become a powerful action group against the government's austerity moves and regularly stage protests at the parliament building in the capital Kiev. (tl/ez)