A Russian missile blasted a crater close to a nuclear power plant in Southern Ukraine Monday, damaging nearby equipment but not hitting its three reactors — a reminder that despite battlefield setbacks, Moscow can still menace Ukraine’s four active nuclear plants.

The missile struck within 300 meters of the reactors at the South Ukraine nuclear power plant near the city of Yuzhnoukrainsk in Mykolaiv oblast ‚— 250 kilometers west of another nuclear complex, the Zaporizhzhia plant, which has been a focus of global concern and where the United Nations sent a team to stabilize the situation earlier this month.

The reactors at the South Ukraine complex were working normally and no employees were injured, Ukraine’s national nuclear company Energoatom said. But the strike renewed fears that Russia’s nearly 7-month-old invasion of Ukraine could result in a nuclear catastrophe.

Unlike the Zaporizhzia complex, which lies in an active battlefield, the South Ukraine plant sits far from frontline fighting and Monday’s strike appears to demonstrate Russia’s long reach, and how easily it could inflict a disaster by attaching such a plant.

Following recent battlefield upsets, Russian President Vladimir Putin threatened last week to ratchet up attacks on Ukrainian infrastructure. Throughout the war, Russia has battered energy systems relied on by civilians with artillery, briefly set up a base in the Chernobyl exclusion zone, and has occupied the Zaporizhzhia plant, Europe’s largest nuclear power station, for months, raising fears that an accident would ensue.

The industrial complex that includes the South Ukraine plant sits along the Southern Bug River about 300 kilometers south of the capital, Kyiv. The attack caused the temporary shutdown of a nearby hydroelectric power plant and shattered more than 100 windows at the complex, Ukrainian authorities said. The UN’s International Atomic Energy Agency said three power lines were knocked offline but later reconnected.

Ukraine’s Defense Ministry released a black-and-white video showing two large fireballs erupting one after the other in the dark, followed by incandescent showers of sparks, at 19 minutes after midnight. The ministry and Energoatom called the strike “nuclear terrorism.”

Before Russia sent forces streaming into Ukraine in February, nuclear plants produced more than half of Ukraine’s electricity, the second-highest share among European nations after France. That heavy reliance has raised fears about further energy disruptions during the winter, and about the threats to the nuclear plants around the country.

Shelling has repeatedly cut off the Zaporizhzhia plant’s transmission lines, leading operators to shut down all six of its reactors to avoid a radiation disaster.

“There is no other way to characterize this except for nuclear terrorism,” Petro Kotin, the head of Energoatom, told Ukrainian national television on Monday. He said that although the heavily fortified concrete buildings that house nuclear reactors are built to withstand a plane crash, the blast from the overnight strike would have been powerful enough to have damaged the containment structures, had the missile struck closer.

Before the Russian invasion, Ukraine had 15 working reactors at four nuclear plants built during the 1970s and 1980s when Ukraine was still a Soviet republic: the South Ukraine and Zaporizhzhia plants, in the south, and the Khmelnytskyi and Rivne plants, in the west. The Chernobyl plant in the north, the site of the 1986 nuclear accident, is decommissioned but engineers still safeguard nuclear waste at the site — even during the weekslong occupation by Russian troops this spring.