Ukraine Digs for Survivors in Rubble of Residential Attacks by Russian Missiles

“It was a missile strike. And everyone who gives orders for such strikes, everyone who carries them out targeting our ordinary cities, residential areas, kills absolutely deliberately,” Mr. Zelensky said in a video posted online late Sunday night.

Artillery duels and airstrikes have remained intense, especially near the front lines in eastern Ukraine, even as some analysts say Russia appears to have paused the advance of its ground forces. Mr. Zelensky said there were 34 Russian airstrikes Sunday alone.

Russia has said its forces don’t target civilians, and reporters saw victims in uniform pulled from the rubble. The Russian Ministry of Defense said on Monday that it targeted infrastructure used by Ukrainian forces in Chasiv Yar.

After capturing the entire eastern Luhansk region, Moscow has placed its forces on an “operational pause,” said the Institute for the Study of War, as Russia shifts its focus toward taking the Donetsk region, which with Luhansk makes up the Donbas area.

Authorities in the occupied parts of eastern Ukraine have also started expropriating port infrastructure, as they seek to export stolen and other grain from the country’s internationally important farm fields.

Both sides have taken heavy losses as the conflict has become a war of attrition, defined by relentless volleys of heavy artillery and missiles. Oleg Kotenko, commissioner for the International Commission on Missing Persons, told Suspilne, a Ukrainian public radio outlet, that his organization believes more than 7,000 members of the Ukrainian military were unaccounted for.

As the West ferries long-range weaponry into Ukraine, Russia’s military has stepped up missile strikes on positions that are far from the front lines.

Moscow also has relied on what it has called long-range precision strikes on military bases and infrastructure away from the front lines. Some have led to mass casualties, such as at a train station in Kramatorsk, where nearly 60 were killed and more than 100 injured, and a shopping mall in Kremenchuk, killing at least 20.

British intelligence previously said Russia’s shortage of more modern precision strike weapons would likely result in further civilian casualties.

Russian missile strikes continued Monday morning as Ukrainian officials reported damage to civilian areas in both the north and south of the country. Ukrainian officials also accused Moscow of using cluster munitions, which have been banned by many countries because of the wide, indiscriminate destruction they cause.

Oleh Synyehubov, governor of Ukraine’s Kharkiv region, said Russian missile attacks began there around 3:40 a.m. on Monday. One missile destroyed a school, he said, while another hit a six-story residential building. At least three were killed, he wrote on the Telegram messaging app, and some 31 people have been hospitalized.

“Only civilian structures—a shopping center and houses of peaceful Kharkiv residents—came under the fire of the Russians,” he wrote.

Though strikes have continued across the country, the bulk of Moscow’s firepower has been trained on the Donetsk region. Russia and pro-Russian separatist forces already control part of the province, including the capital, Donetsk. Capturing the rest of the province would give Moscow full control of the Donbas area, which the Kremlin made its priority after pulling its forces out of central Ukraine in late March.

The Ukrainian Ministry of Defense said Monday that several parts of the Donetsk region had been hit with barrel bombs, whose use in populated areas is banned by the United Nations. In addition, the ministry said there were “signs of enemy units preparing to intensify combat operations in the Kramatorsk and Bakhmut areas.”

Pavlo Kyrylenko, head of the Donetsk regional military administration, said 593 civilians have died in the Donetsk region, and another 1,550 have been injured, since the full-scale invasion began in February.

Ukrainian forces, meanwhile, are preparing for a counteroffensive in the southern Kherson region, said the Institute for the Study of War, a U.S. think tank, and officials have been advising civilians to leave the region. Neither side has made significant territorial gains in recent days, according to the British Ministry of Defense.

On Monday, Europe was bracing for a sharp reduction in the flow of natural gas from Russia as the Nord Stream pipeline was scheduled to shut down for 10 days of annual maintenance. European governments fear the pipeline, the main artery for Russian gas to reach Germany, won’t come back online after Moscow already reduced gas deliveries through the conduit by 40% in recent weeks.

Moscow has blamed the reductions on Western sanctions that it says are depriving the pipeline of crucial equipment, including a turbine that has been in Canada for repairs. Ukrainian officials criticized Canada for recently deciding to return the turbine to Germany for use in Nord Stream. Berlin wants to return it to Russia, saying the move would show that Moscow has been using the turbine as an excuse for a political decision to cut gas deliveries to Europe.

In a joint statement released Sunday, the Ukrainian ministries of Energy and Foreign Affairs accused Canada of bending “the sanctions regime to the whims of Russia. This dangerous precedent violates international solidarity.”

Mr. Zelensky added Monday night that “every concession in such conditions is perceived by the Russian leadership as an incentive for further, stronger pressure.’’

Ukrainian military intelligence said Russia and its local allies are stepping up their efforts to export grain from Ukraine’s occupied east. Authorities there have created a company and nationalized exporting infrastructure in the port of Berdyansk, said Ukraine’s Directorate of Intelligence of the Ministry of Defense.

Ukraine’s massive grain exports have been a key international flashpoint in the conflict, as Russia blocks the country’s ability to export its wheat, corn and sunflower oil through the Black Sea. That has put pressure on grain prices around the world, adding to the food-price inflation that is affecting consumers from the U.S. to Somalia.

Authorities in Ukraine’s occupied Zaporizhzhia region, in the southwest of the country, have created an organization called Gosudarstvennaya Unitarnaya Kompaniya, GUK, or State Unitary Company, to organize the export of grain from the area, the military-intelligence officials said.

The organization sets the price at which it buys grain from local farmers at 9,000 Russian rubles for a metric ton of wheat and 7,000 for barley, the military-intelligence officials said—prices that are well below current market prices, according to grain brokerage Maxigrain. Farmers in occupied parts of the country have said their grain has been stolen and are having to sell other produce at knocked-down rates.

Occupying authorities have also nationalized a grain elevator and the loading complex at Berdyansk. The owners of these assets couldn’t be reached for comment.

The Wall Street Journal has reported that farmers have had land seized by groups linked to occupying authorities and a group claiming to work for a former Russian minister. Farmers also say they have had grain stolen from them. Military intelligence said that vessels are already arriving in Berdyansk to take out grain.

On Monday, Russian President Vladimir Putin discussed grain exports in a call with his Turkish counterpart, Recep Tayyip Erdogan, who said it is time for the United Nations to act on plans to establish secure corridors via the Black Sea, according to a statement from the Turkish presidency.

Mr. Erdogan discussed the proposed grain corridors with Mr. Zelensky in another call, in which the Turkish president said Ankara is working to ensure Ukrainian grain could reach the global market.

Mr. Putin had a separate call with Belarusian leader Alexander Lukashenko in which they denounced the “illegal” restrictions imposed by Lithuania after Vilnius invoked Western sanctions to block some Russian goods from entering the Russian exclave of Kaliningrad. The Kremlin said the two leaders discussed “possible joint steps” to address what Russian officials called a blockade by Lithuania, but didn’t elaborate.

In Moscow, Mr. Putin signed a decree allowing all residents of Ukraine to apply for Russian passports, extending a program that was available only in occupied areas.

Russia has already distributed passports to residents of the self-proclaimed Donetsk and Luhansk people’s republics, the Russian-controlled statelets created in eastern Ukraine in 2014. Mr. Putin had also extended the program in late May to the occupied areas of the Kherson and Zaporizhzhia regions in southern Ukraine.

Write to Ian Lovett at ian.lovett@wsj.com, Mauro Orru at mauro.orru@wsj.com and Alistair MacDonald at alistair.macdonald@wsj.com