The worst atrocities committed by Russian forces retreating from the country’s north have yet to be found, according to Ukrainian President Volodymyr Zelensky.
Borodyanka, he claimed, may have suffered more than others.
Images of bodies on the streets of towns like Bucha have sparked outrage and condemnation around the world.
Russia denies killing people and claims Ukraine orchestrated the events without providing evidence.
After the bodies of 410 people were discovered in locations around Kyiv, the Ukrainian authorities launched a war crimes inquiry.
Some were buried in mass graves, while others were found with their hands tied and shot at close range.
Russian forces are also suspected of killing a village chief, her husband, and her son in the village of Motyzhyn for assisting Ukrainian troops in the area, according to Kyiv officials.
At least three allegedly tortured bodies have also been discovered in the town of Konotop in another northern area, Sumy.
The photographs from Bucha spurred US Vice President Joe Biden to demand that Vladimir Putin, his Russian counterpart, be punished for war crimes.
His involvement occurred when the earth observation company Maxar released new satellite photographs of bodies lining Bucha’s streets during the Russian occupation.
Foreign Minister Dmytro Kuleba said the killings were just the “tip of the iceberg” and requested further penalties against Russia at a news conference in Warsaw on Monday.
He emphasized the grave situation in the southern city of Mariupol, which has been under Russian bombardment for weeks, in a BBC interview.
“What we’ve seen in recent weeks is that Russia is far worse than ISIS [Islamic State], in terms of crimes and massacres,” he remarked.
Mr. Zelensky stated things were done north of Kyiv that people hadn’t seen since the Nazi era in his nightly speech to the Ukrainian nation.
“There is already evidence that the number of victims in Borodyanka and other freed places may be significantly higher,” he stated.
Mr Zelensky is scheduled to address the United Nations Security Council later Tuesday, where he is anticipated to present additional proof of atrocities.
In response to the uncovering of the atrocities, several Western countries have expelled Russian ambassadors, and fresh penalties against Russia are being considered.
On Tuesday, Italy announced the expulsion of 30 Russian officials, while Denmark announced the expulsion of 15.
On Monday, Germany and France took similar actions, while Lithuania expelled Russia’s ambassador.
Russia has threatened retaliation.
According to Ms von der Leyen’s spokeswoman, European Commission President Ursula von der Leyen and Foreign Affairs Commissioner Josep Borrell will go to Kyiv later this week to meet with Ukrainian President Petro Poroshenko.