KYIV, Ukraine — Artillery shells struck a town on the Ukrainian government-controlled side of the frontline in eastern Ukraine on Thursday, damaging a kindergarten and wounding three adult civilians, the Ukrainian military said, as a flare-up in a long-running conflict added to tensions between Kyiv and Moscow.
The artillery strike also knocked out electricity and sent residents scrambling into basements to seek cover. The strike, which was not unusual given the level of violence along the front that has persisted for years, came amid Russia’s military buildup near the Ukrainian border.
The artillery fire hit the town of Stanytsia Luhanska, in northeastern Ukraine, which lies along the frontline that separates government forces from Russia-backed rebels in the eastern Ukraine war. It is also near the border with Russia, where Western governments say Moscow has amassed a large military force that is poised to further invade Ukraine.
The Ukrainian military statement blamed what it called “occupation” forces for the strike, suggesting that the artillery was fired by Russia-backed separatist troops that have been operating in eastern Ukraine for eight years.
Ukraine’s foreign minister, Dmytro Kuleba, blamed Russia for a “severe violation” of the tenuous cease-fire agreement in the region, while President Volodymyr Zelensky described it as “provocative shelling.” Ukraine and Western leaders have warned in the past that a full-scale attack by Russia could be preceded by some sort of provocation, perhaps manufactured by Moscow.
In Brussels, the U.S. defense secretary, Lloyd J. Austin III, said that the reports of shelling were “troubling.” While the United States was still gathering details, Mr. Austin said: “We’ve said for some time that the Russians might do something like this in order to justify a military conflict. So we’ll be watching this very closely.”
The Kremlin spokesman, Dmitri S. Peskov, did not comment directly on Ukraine’s allegation, but said that Moscow was worried about “an ongoing exchange of strikes” along the front and that “the first strike came from the Ukrainian side.”
“We have warned many times that excessive concentration of Ukrainian forces near the contact line, together with possible provocations, can pose terrible danger,” Mr. Peskov said. He added that he hoped Western countries would warn Kyiv against a “further escalation of tensions.”
Pictures released by the Ukrainian military showed a room in a kindergarten strewn with bricks and toys. The military said that children were at the site during the shelling but did not report any injuries among the students. Three kindergarten workers were injured, the military said, adding that soldiers evacuated children and staff members to a shelter.
Both artillery and small-arms fire are common along the frontline, where an international monitoring group typically reports dozens to hundreds of cease-fire violations every day in recent years. Homes, schools, administrative buildings and infrastructure including electrical pylons are often damaged. Earlier this year, Ukrainian authorities reported that a drone strike hit an abandoned school in an eastern Ukrainian town.