Ukrainian national guardsmen opened fire on a crowd outside a town hall in eastern Ukraine and an official for the region's insurgents said there were fatalities.
The bloodshed in the town of Krasnoarmeisk occurred hours after dozens of guardsmen shut down voting in a referendum on sovereignty for the region.
A photographer who witnessed the shooting said two people were seen lying unmoving on the ground and insurgent leader Denis Pushilin said there were an unspecified number of deaths.
Several hours earlier, guardsmen came to the town about 20 miles from the regional capital, Donetsk, and dispersed referendum voting that was taking place outside the town hall before taking control of the building.
In the evening, more guardsmen arrived and a scuffle broke out. Then the guardsmen fired shots.
Eastern Ukraine has been gripped by unrest for the past month as pro-Russia insurgents occupied police stations and government buildings. Ukrainian forces have mounted a limited offensive to try to drive them out.
The Donetsk and Luhansk regions conducted referendums on declaring the regions as so-called sovereign people's republics.
Leaders of the vote, regarded as illegitimate by the central government and the West, say that sometime after the referendum, a decision will be made on whether to remain part of Ukraine, declare independence or seek annexation into Russia.