A mortar reportedly blew up at about 06:00 Kyiv time on July 6 amid military drills at Ukraine's Rivne training ground, as a result of which three Ukrainian troops were killed and nine others received injuries of varying severity.
The information was confirmed by the Ministry of Defense of Ukraine, the TSN TV news service reported on July 6.
All those servicemen who were standing next to the weapon were either killed or wounded, the latter were taken to hospital.
The cause behind the incident is being investigated, TSN said.
In turn, the press service of the Land Forces of Ukraine's army has reported that three servicemen were killed and nine were wounded during tactical exercises of brigades at the 233rd Rivne training range.
"At 05:55 this morning, three soldiers died from fatal wounds and nine sustained injuries of varying severity amid live firing exercise at the 233rd Rivne range," the report said.
According to preliminary conclusions, the casualties were due to an explosion of a mortar.
The Commander of the Ground Forces of the Armed Forces of Ukraine has decided to suspend the drills.
An official investigation has started to determine the real causes behind the incident.