Hundreds of coal miners have marched through Ukraine's capital demanding that the government stop buying fuel from abroad and put an end to the closing of mines.
The miners demanded the resignation of Coal and Energy Minister Volodymyr Demchyshyn as they banged their helmets with sticks and waved flags.
The April 23 protest march went from government headquarters to the Coal and Energy Ministry building, which was guarded by dozens of police.
Demchyshyn, who is in the United States for an international energy conference, said he was ending his trip early to return to Kyiv and deal with the protest.
The government says it was forced to buy winter coal supplies from abroad because of the war against Russian-backed separatists in eastern Ukraine where most of the country's largest mines are located.
The miners held an annual congress in Kyiv on April 22, one day before the protest.