The mayor of Kurchatov, a Russian town near the border with Ukraine, said that Ukrainian forces had launched a stunning incursion into the country and were advancing toward a nuclear power plant Friday, according to the Washington Post.

The news comes as civilians continue to evacuate the border province of Kursk amid fears that the conflict will continue to creep onto Russian soil. Military commanders have also scrambled to send reinforcements from across the country to the region, where the fighting has been concentrated. On Monday, Ukrainian forces began the offensive operation in Kursk, an Oblast on Ukraine’s northeastern border with Russia, capturing over 20 Russian villages and parts of the city of Sudja, the Washington Post reported. The Azerbaijani outlet Vesti.az reported on Friday evening that the mayor of Kurchatov, Igor Korpunkov, said in a statement on Telegram that “fighting is several dozen kilometers” from the nuclear plant.

“The situation is tense, a state of emergency is in effect. However, all services and enterprises, including the city administration, are operating normally. I am personally in the city, at my workplace, monitoring the situation,” Korpunkov added.

The International Atomic Energy Agency wrote in a statement to Russian state media organ TASS, on Friday that the IAEA, “is following reports about recent developments and has channels of communication open to both sides of the conflict. At this point there is no reason for concern with regard to nuclear safety and security.”

“IAEA Director General Rafael Mariano Grossi reiterates that all nuclear power plants, regardless of where they are situated, should never be a target of an armed attack,” the agency added.

The Institute for the Study of War reported Thursday that Ukrainian forces had penetrated as deep as 35 kilometers (22 miles) into Russian territory. Russian authorities declared a federal emergency in Kursk on Friday night as Ukrainian forces continued to advance, knocking out an entire Russian reinforcement convoy on the E38 highway, according to the Guardian.

Unconfirmed reports from later in the day, Friday, from the Ukrainian outlet OBOZ.UA claim that a Ukrainian drone hit the substation of the plant, knocking out power in Kurchatov.

Pentagon spokesperson Sabrina Singh told reporters during a Thursday press conference that Ukraine’s advance into Russia “were within the U.S. policy,” referring to Ukraine’s use of U.S. supplied weaponry in Russian territory.