The men were seen registering their names with the Russian embassy's guards who asked them for proof of military service, a report said.
The Mariupol City Council said it had evidence that Russians buried bodies "in several layers."
The actual number of deaths and injuries among children could not be determined as some cities in Ukraine continue to see intense combat.
The newly released intercepted phone call is the latest in a string of reports about demoralized and fatigued Russian troops turning on their commanders and generals as the war stretches into its eighth week.
Ukraine's former prime minister also warned that Russia may be aiming to achieve any victory by May 9.
"A passport with the surname ‘Navalny’ lies next to the dead body on the ground," Alexei Navalny wrote on Twitter.
The soldier, whose name was not released, had signs that he tried to take his life by cutting his veins.
“Putin has already lost this war. I want to say that and I want to say it loudly. He’s lost the war. Now he’s fighting to win one battle so he can pursue peace,” the former ambassador said.
The Ukrainian man has been posting updates about the location of his AirPods - which were stolen by a Russian soldier - on his Instagram account.
Col. Ivan Grishin was the 23rd Russian commander to have been killed in the war in Ukraine.
President Joe Biden will appear in New Hampshire to discuss his one trillion-dollar infrastructure bill
Ukrainian MP Lesia Vasylenko said the cities of Ochakiv and Mykolaiv were hit with cluster bombs.
A newly released intercepted phone call recorded a Russian soldier saying he could be paid as much as three million if he is injured in the war.
The deputy chairman of Russia's Security Council previously threatened the use of nuclear weapons if Finland and Sweden join NATO.
Rinat Akhmetov's net worth reached $15.4 billion in 2013.
At least five people were wounded during the shooting incident, according to a Ukrainian MP.
The Russian soldier compared the recent bombing to a series of attacks on Russian apartments in 1999. It has been speculated that the attacks were carried out by the Russian government.
“This is going to get stronger and rougher, and what really needs to happen is Ukraine is not asking for American men and women to fight. All they’re asking for is the weapons to defend themselves,” House Minority Leader Kevin McCarthy said.
Concerns are mounting among Ukrainian experts that Russia's sunken Moskva battlecruiser may have been carrying nuclear weapons onboard.
Russia has warned the United States to stop arming Ukraine or provoke "unpredictable consequences" after losing the flagship of its Black Sea fleet allegedly to Ukrainian missiles.
Russian President Vladimir Putin is currently the richest world leader, with a net worth of $70 billion.
A Russian soldier told his mother that he only received the basic pay instead of the promised special pay.
