SOFIA (Reuters) - A blast at a military plant in central Bulgaria killed one and injured four others on Saturday, the interior ministry said in a statement.
The ministry said the accident occurred during a planned experimental production test at the military complex in the village of Anevo -- part of the state-owned arms producer VMZ Sopot.
Bulgarian national radio and several other media reported that the man killed and two of the injured were U.S. citizens. The interior ministry was unable to confirm the nationality of the victims when contacted by Reuters.
"There is no panic in the town (of Sopot), there is no danger of new explosions," Sopot mayor Veselin Lichev, who rushed to the complex a few minutes after the explosion, told Bulgarian national radio.
A series of powerful blasts at an explosives plant in northwestern Bulgaria killed 15 employees and injured three others last October, just two months after government officials warned of serious safety breaches at the factory.
(Reporting by Angel Krasimirov; Editing by Toby Chopra)