World leaders have expressed outrage over the killing of civilians in Bucha, a suburb of the Ukrainian capital, Kyiv. They called on Monday for investigations into the actions of Russian forces and what some say are war crimes.

US President Joe Biden avoided using the word "genocide." But he again called Russian President Vladimir Putin a "war criminal." Biden said he would push for more sanctions.

Some allies joined in the call for more economic penalties. Prime Minister Kishida Fumio said Japanese must condemn acts that could violate international laws.

The President of the European Commission spoke with Ukrainian President Volodymyr Zelenskyy about what she called the "murder of civilians." Ursula von der Leyen said the European Union would send investigators to document war crimes.

Officials in Germany and France have also responded. They joined those in other European countries in deciding to expel Russian diplomats.