Iran’s Defense Ministry says an accident at one of its research units in the Parchin military complex near the capital, Tehran, has killed one engineer and injured another employee.

“On Wednesday evening, in an accident that took place in one of the research units of the Defense Ministry in the Parchin area, engineer Ehsan Qadbeigi was martyred and one of his colleagues injured,” the ministry said on Thursday.

It said investigations are underway to determine the cause of the accident, without giving further details.

Parchin, a military site located southeast of Tehran, houses several industrial and research units.