Ukraine's Interior Ministry said Thursday at least five people were killed after a member of the national guard opened fire at an aerospace factory in the east of the country.
The shooting took place in the city of Dnipro. The attacker opened fire with a Kalashnikov assault rifle and immediately fled the scene, the ministry said.
"As a result, five people died and another five were injured," the statement added.
The incident occurred around 3:40 a.m. local time (1:40 a.m. GMT), it said, when the shooter was being issued a weapon at the beginning of a shift.
The Yuzhmash facility is an aerospace factory that produces and tests material related to defense, aeronautics and agriculture, according to its website.
The ministry said the shooter was born in 2001 and "has been detained by police" in the Dnipro region, the country's Interior Minister Denys Monastyrsky wrote on Facebook.
"The motives for the crime are not yet known," the statement said, adding that a commander of the National Guard, Nikolai Balan, had been dispatched to the scene.
Bullying rituals plagued militaries of former Soviet countries in the 1990s – a trend which rights groups say has improved – but regularly result in suicides or murders.