KIEV, Ukraine — A Ukrainian chemistry student has been killed by exploding bubble gum that tore off half of his face, police said Thursday.

Vladimir Likhonos, a student at a regional branch of the Kyiv Polytechnical Institute, is thought to have accidentally dipped his chewing gum into explosives he was using for his studies, police spokeswoman Elvira Biganova told The Associated Press. She said the 25-year-old mistook the powder for citric acid, which he often added to prolong the gum's taste.

Likhonos, from the town of Konotop, in northeast Ukrainian, blew off his entire jaw and most of the lower part of his face in Saturday's accident. Medical workers who arrived on the scene attempted to treat his injuries but were unable to save him.

"Even some of our seasoned officers, who have seen a thing or two, even they were pretty badly shaken up by what they found," Biganova said.

On the table where Likhonos had been working police found about 3.5 ounces (100 grams) of the suspected explosive -- a powder that resembles citric acid but has yet to be identified, she said.

"Anybody could have mixed them up," Biganova said.

A bomb squad was dispatched to determine the nature of the substance, which was deemed too volatile to transport, Biganova said.