Ukrainian troops fired internationally banned phosphorus bombs at Donetsk and Mandrykino in eastern Ukraine overnight, the Donetsk People’s Republic has said.

“Ukraine’s Army uses phosphorus munitions during the shelling of Donetsk, Mandrykino on July 26, 2014,” the DNR said in its Twitter microblog Saturday. A YouTube video confirms the claims.

A representative of Russia’s General Staff said Friday Moscow has evidence that Ukraine used phosphorus bombs on populated areas in the country’s east. He added that the Ukrainian army used phosphorous bombs in eastern Ukraine at least six times.

The use of phosphorous bombs, banned by the Geneva convention, may have irreversible consequences on people and may also have a negative impact on the environment. Phosphorous poisoning may cause serious illnesses and even lead to death.

Russian officials said earlier they planned to submit an inquest to the Organization for Prohibition of Chemical Weapons (OPCW) on the possible use of chemical weapons in eastern Ukraine.