Fighting around a Ukrainian nuclear plant heightens safety fears.

DRUZHKIVKA, Ukraine — Fighting raged on Saturday near a sprawling nuclear power plant in the south of Ukraine, despite warnings from nuclear safety watchdogs earlier this week that conditions there were posing risks and “out of control.”

The Russian military has been using the Zaporizhzhia plant, Europe’s largest, as a base to assault the Ukrainian-controlled town of Nikopol across the river.

On Saturday it fired a volley of Grad rockets that damaged 11 apartment buildings and 36 privately owned houses, and wounded three people, the Ukrainian military said.

The assault also knocked out electricity, water and natural gas supplies in the town, where residents have been fleeing from the artillery attacks and attendant risk of radiation, the Ukrainian military said.

Russian forces began staging artillery attacks from the plant about a month ago, and the Ukrainian military has said it cannot shoot back because of concerns that it would hit a reactor at the plant, igniting a radiation catastrophe.

Ukraine has also accused the Russians of setting off explosions at the plant intended to unnerve European allies about nuclear safety and discourage arming Ukraine.

Outrage over nuclear safety violations — Rafael Grossi, the director general of the United Nations’ nuclear watchdog, said on Tuesday that “every principle of nuclear safety has been violated” — has done nothing to dislodge the Russian Army from the site. Fighting has continued daily, with explosions in the early afternoon on Friday. Mr. Grossi called conditions at the plant “out of control.”

Mr. Grossi said he was far more worried about Zaporizhzhia than he was about Chernobyl, the site of the 1986 nuclear disaster, also in Ukraine, that radiated the surrounding area and imperiled Europe.

“Chernobyl, I think we are fine,” said Mr. Grossi, noting that his agency had inspected the plant regularly and had restored sensors for radiation monitoring and other detection devices.

But the I.A.E.A. has been unable to access key parts of the reactors at Zaporizhzhia, as the occupying Russian force and surrounding shelling make it too dangerous for inspectors. That raises the prospect that if damage is done to the facility, it may be difficult, at best, to assess the danger, he added.

In his nightly address to Ukrainians, President Volodymyr Zelensky on Friday highlighted what he called the “brazen crime” of the Russian military using the nuclear power plant as cover.

“The occupiers created another extremely risky situation for everyone in Europe,” Mr. Zelensky said, citing the explosions earlier in the day at the plant. “This is the largest nuclear power plant on our continent. And any shelling of this facility is an open, brazen crime, an act of terror.”

David E. Sanger contributed reporting from Weston, Vt.