The death toll climbed to 40 on Monday from a weekend missile strike on a high-rise apartment complex in the central Ukrainian city of Dnipro, according to Ukrainian officials.

At least three children were among those killed, officials said. Another 70 people were injured.

The death toll is expected to rise as 30 people remain unaccounted for, officials said.

On Saturday, a missile slammed into a block of high-rise apartment buildings in the central Dnipro. While Ukrainian officials blamed Russia for the strike, one of the deadliest attacks since the war began, the Kremlin denied Russia was involved.

“The Russian armed forces do not strike residential buildings or social infrastructure, they strike military targets,” Kremlin spokesman Dmitry Peskov told reporters Monday.

-ABC News' Matt Gutman

The death toll from a Russian missile strike on a block of high-rise apartment buildings in the central Ukrainian city of Dnipro rose to 29 on Sunday.

Amidst the devastation, rescuers pulled one woman alive from the rubble on Sunday and officials said she was saved by a cocoon of concrete that surrounded her.

The survivor was rescued from a block of apartment buildings hit by a Russian missile on Saturday in the city about 500 miles southeast of the capital of Kyiv.

Ukrainian President Volodymyr Zelenskyy said a child was among those killed in the Dnipro missile attack.

Despite Sunday's rescue, emergency workers said the hope of finding more survivors is fading.

The rocket attack reduced part of a high-rise apartment building to a pile of rubble that was still smoldering on Sunday. Noxious fumes from burning couches, curtains and TVs emanated from the pile as firefighters sprayed water hoses on it and rescue workers dug through the debris with their bare hands, an ABC News crew in Dnipro reported.

In addition to the now 29 killed in the attack, more than 70 people were injured, Ukrainian officials said. The strike left hundreds of apartments uninhabitable, officials said.

Emergency crews brought in cranes Sunday to help move large pieces of debris.

As the rescue operation went on Sunday, periodic moments of silence were called for so rescuers could listen for cries for help from people feared missing in the rubble.

-ABC News' Matt Gutman

Five people were killed and at least 27 were wounded in a Russian attack in Dnipro in central Ukraine, according to the governor.

An apartment block was struck and at least two children are among the injured, according to the deputy head of the president’s office.

-ABC News’ Yulia Drozd

Kyiv mayor Vitali Klitschko said explosions occurred in different districts on both banks in the city on Saturday morning and, in one of the districts, fire broke out in a non-residential area.

There were no casualties as a result of the attack that happened at approximately 6 a.m. but 18 residential houses were damaged in the region, according to the governor Oleksiy Kuleba.

The spokesman for the Ukrainian Airborne Forces, Yuri Ignat, told ABC News that Ukrainian authorities think it could have possibly been a ballistic attack by Russia but could not confirm this.

"Most likely, these are missiles that flew along a ballistic trajectory from the north. Ballistics are not available for us to detect and shoot down," Ignat said on Ukrainian television.

-ABC News' Yulia Drozd

U.S. President Joe Biden made an unannounced visit to war-torn Ukraine on Monday, arriving in Kyiv as Washington signals its ongoing support ahead of the one-year anniversary of Russia's invasion.

Biden's visit came ahead of a planned meeting with NATO allies in Poland. He is expected to give a speech at the Royal Castle Arcades in Warsaw on Tuesday evening to offer an appraisal of international support during the first year of the war and to address "how we will continue to stand with the people of Ukraine for as long as it takes," White House spokesperson Karine Jean-Pierre said in a statement earlier this month.

Biden also plans to meet in Poland with leaders of the Bucharest Nine, a group of eastern NATO allies formed in 2015 in response to Russia's annexation of Ukraine's Crimean Peninsula.

Ukrainian President Volodymyr Zelenskyy made a dramatic visit to the United States in December, his first known international trip since the Russian invasion began in February 2022. Zelenskyy met with Biden at the White House in Washington, D.C., before addressing members of U.S. Congress on Capitol Hill.