Three people died on Thursday, June, 28, after a blast rocked a test facility which belongs to Ukrainian state-run arms manufacturer Ukroboronprom in Sumy region in northern Ukraine.
Among the deceased was a NATO representative, the regional prosecution said, according to UNIAN.
Another two people received injuries and were rushed to a hospital. Their health condition was described as stable.
All three killed were citizens of Ukraine. Preliminary reports stated a rocket went off while the projectiles were being unloaded.
The NATO representative was present at the facility as part of the Alliance's special mission, which included help in military ammunition disposal.
According to Ukrainian military prosecution, the blast was most likely caused by the negligence of the local stuff. The prosecution initiated a criminal investigation of the incident.