"We are constantly learning from these tests and fully investigating the cause of this error."
U.S. troops accidentally entered a vegetable oil processing plant in Bulgaria during a NATO exercise last month in an incident that led to criticism from an American partner in Eastern Europe and accusations by the industry owner.
U.S. forces stormed a building near an airport in southern Bulgaria that they believe is part of a training ground, the U.S. military said in a statement issued on Tuesday.
But there were Bulgarian citizens who were "conducting private business" in the building, adding, adding that no weapons were fired at any time during the operation.
The incident happened during a NATO-led operation of several US troops on May 11, according to a statement.
Troops imitated the kidnapping and defending of an abandoned airport in the city of Chesnegirovo as part of the plan, the statement said.
"We apologize to the business and its employees," he added. "We are constantly learning from these tests and fully investigating the cause of this error."
The statement did not identify the company, but the Associated Press released a video rented by KIM Engineering Ltd, which showed uniformed soldiers hiding in a gun-like factory.
U.S. troops accidentally attacked Bulgarian oil refinery during a NATO exercise on May 11. KIM Engineering Ltd. / AP
KIM Engineering Ltd manufactures vegetable oil refinery, according to its website, and is located near Chesnegirovo airport.
The owner of the company Marin Dimitrov has now filed a lawsuit in connection with the incident, reports the Associated Press.
He described the raid as "illegal looting of personal property," saying he was upset and humiliated.
"It's like we're robbers, criminals, even though we do normal jobs," Dimitrov said.
"Seven armed soldiers came in, pointing their weapons at the workers," Dimitrov told reporters. "Cameras show the work of raising hands, they say in English let him sit down, my people are really listening, they are very scared."
The incident also angered Bulgarian President Rumen Radev.
Bulgarian television station NOVA quoted Radev as saying on Monday "it is totally unacceptable that the lives and peace of Bulgarian citizens are threatened by the military, whether part of the Bulgarian or foreign military."
Exercising with partners in the Bulgarian region should contribute to building security and trust in mutual protection, not breeding conflict, Radev said, according to NOVA. He also called for a thorough investigation and disclosure of the names of officials responsible for the incident.
More than 7,000 paratroopers from 10 NATO countries participated in the Swift Response 21 tests between May 10 and 14.Laszlo Balogh / AP
Bulgaria and the United States are NATO allies. The bloc has forwarded NBC News to U.S. officials for comment as the program was led by the U.S.
A former Soviet-satellite country, Bulgaria has been a member of NATO since 2004.
A 2020 poll showed that NATO is generally recognized in the alliance, but NATO's positive views have declined sharply in Bulgaria over the past decade. In almost all the countries surveyed, large stocks supported closer ties with the U.S. than in Russia, but Bulgaria was one of two different ones.
However, the U.S. says it has enjoyed "strong security ties" with Bulgaria for more than 15 years. Five years ago, the State Department said the U.S. Provided more than $ 160 million in security assistance in Bulgaria.