Photo from UNIAN

The Ukrainian arm of the world's biggest steelmaker said on Saturday that the state security service had searched its plant in Kryvyi Rih, a week after new Ukrainian President Volodymyr Zelensky criticized the management.

ArcelorMittal has invested about $9 billion in Kryvyi Rih, Ukraine's largest steel mill, which is now under close government scrutiny, as reported by Reuters.

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"Today, Ukrainian Security Service officials arrived at our plant and carried out a search," Alexander Ivanov, the acting head of the mill, said in a statement.

Zelensky, whose party will fight for control over parliament at an election on Sunday, visited his hometown Kryvyi Rih, 350 km southeast of Kyiv, last week.

He called environmental conditions in the town "the biggest ecological problem" in Ukraine and asked ArcelorMittal's officials at a public meeting why the number of cancer patients in the area "should depend on their strategic plans."

The security service said earlier this week that it had launched an investigation into officials of one of the companies in Kryvyi Rih, whose activities caused damage to the environment, without giving the name of the company.

Asked to comment on the search at ArcelorMittal's mill, a security service spokeswoman referred to the previous statement and declined to comment further.

Ivanov, the head of the mill, said the company was ready to work with the authorities and was discussing improvements.