RESCUERS CONTINUE THE SEARCH AT KYIV CHILDREN'S HOSPITAL HIT BY RUSSIAN MISSILE. (PHOTO).

 Rescuers continue the search at Kyiv children's hospital hit by Russian missile

Rescue operations stretched into a second day at a major Kyiv children’s hospital struck by a Russian missile, Ukraine President Volodymyr Zelenskyy said Tuesday, as officials raised the countrywide casualty toll to 42 dead and almost 200 injured in the previous day's intense daytime barrage that smashed into multiple cities.

Zelenskyy said on the social platform X that 64 people were hospitalized in the capital, as well as 28 in Kryvyi Rih and six in Dnipro — both cities in central Ukraine.

It was Russia’s heaviest bombardment of Kyiv in almost four months and one of the deadliest of the war, hitting seven of the city’s 10 districts. The strike on the Okhmatdyt children’s hospital, which interrupted open-heart surgery and forced young cancer patients to take their treatments outdoors, drew an international outcry.

The 10-story hospital, which is Ukraine's largest medical facility for children, was caring for some 670 patients at the time of the attack, Okhmatdyt’s Director General, Volodymyr Zhovnir, said Tuesday. The missile hit a two-story wing of the hospital.

"The building where we conducted dialysis for children with kidney failure or acute intoxication is ruined entirely," he told reporters, estimating the overall damage to the hospital at $2.5 million.

Danielle Bell, the head of a U.N. team tracking human rights violations in Ukraine, said at least two people were killed at the hospital and some 50 people were injured, including seven children.

The casualty figure would have been much higher if patients hadn't been taken to a bunker when air raid sirens first sounded, she added.

Authorities were working to restore the hospital's power and water supply, Zhovnir said.

Kyiv city administrators declared Tuesday an official day of mourning. Entertainment events were prohibited and flags were lowered in the capital.

Russia denied responsibility for the hospital strike, insisting it doesn’t attack civilian targets in Ukraine despite abundant evidence to the contrary, including Associated Press reporting.

Kremlin spokesman Dmitry Peskov on Tuesday repeated that position, pointing to a Russian Defense Ministry statement that blamed a Ukrainian air defense missile for partially destroying the hospital.

Bell, the head of the U.N. team, dismissed that argument. She said an assessment of video footage and findings on site indicated the hospital "took a direct hit, rather than receiving damage due to an intercepted weapons system."

The hospital likely was struck by a Russian Kh-101 cruise missile, Bell said. Ukrainian officials said the same.

The bodies of three more people were found Tuesday under the rubble of a residential building in the Shevchenkivskyi district of Kyiv, officials said, bringing the death toll in the single building to 10.

The Russian onslaught Monday came on the eve of a NATO summit in Washington where alliance countries are expected to pledge new military and economic support for Ukraine.

Russian President Vladimir Putin, meanwhile, was hosting India’s Prime Minister Narendra Modi in Moscow.

New Delhi’s importance as a key trading partner has grown since the Kremlin sent troops into Ukraine in February 2022.

Zelenskyy was deeply critical of Modi’s visit, saying on X late Monday: "It is a huge disappointment and a devastating blow to peace efforts to see the leader of the world’s largest democracy hug the world’s most bloody criminal in Moscow on such a day."

Meanwhile, Russian military and regional officials said Tuesday that Ukrainian drones targeted six Russian regions overnight, in what appeared to be a bigger-than-usual aerial attack by Kyiv's forces.

Russia’s Defense Ministry said air defense systems in five Russian southern and western regions "destroyed and intercepted" a total of 38 Ukrainian drones.