A Ukrainian chemistry student was killed when a stick of chewing gum apparently exploded in his mouth, Ukrainian media report.

RIA Novosoti, the Russian news agency, says the incident occurred while the unidentified 25-year-old student at Ukraine's Kiev Polytechnic Institute was working at a computer at his parents' house in the city of Konotop.

"A loud pop was heard from the student's room," ukranews.com reports, quoting an aide to the police chief . "When his relatives entered the room they saw that the lower part of the young man's face had been blown off."

The report says a forensic examination found that the gum was covered with an unidentified chemical substance, thought to be some type of explosive material.

Investigators found that the student often dipped his chewing gum into a packet of citric acid and had inadvertently dipped it instead into a similar-looking packet holding explosive material that was also on his desk.

Local police feared the substance might explode if they sent it to Kiev for analysis, so experts from the capital have been summoned to Konotop, RIA Novosti reports.

(Posted by Doug Stanglin)