Prime Minister Sanna Marin (SDP) and President Sauli Niinistö on Sunday expressed support for war crimes investigations in Ukraine.
Marin said alleged attacks on civilians in Ukraine must be investigated as war crimes. She condemned atrocities allegedly committed by Russian forces near Kyiv before withdrawing from the region.
Taking to Twitter, the PM said war crimes need to be investigated and perpetrators brought to justice.
Marin tweeted she was shocked by the "cruel and savage acts" reported as Russian troops have left Bucha, near Kyiv, as well as other regions in Ukraine. "We won't close our eyes, we won't be silent, we won't forget," she wrote.
Ukraine's Defence Ministry is blaming Russian forces for the indiscriminate slaughter of civilians in Bucha. The town's mayor claims some 280 bodies are buried in a mass grave in the city.
Finnish President Sauli Niinistö also took to social media on Sunday to demand justice for killed Ukrainian civilians.
"Reports of Russian forces' cruelty and civilian killings in Ukraine are deeply unsettling. Civilian war crime victims in Bucha, Irpin and other parts of Ukraine deserve justice. Finland supports the role of the International Criminal Court in investigations," Niinistö posted on Facebook.