She made the statement during her speech at the Munich Security Conference on February 18.
"The US has formally determined that Russia has committed crimes against humanity," Harris said.
"And I say to all those who have perpetrated these crimes, and to their superiors who are complicit in these crimes, you will be held to account," she added.
In addition, Harris, who previously worked as a lawyer and headed the California Department of Justice, also reaffirmed the US' commitment to the rule of law and accountability and support for Ukraine.
"For the United States, we will continue to support the judicial process that is underway in Ukraine and that is being conducted by international investigators because justice needs to be served... Let us all agree: on behalf of all the victims, both known and unknown, justice must be served," she urged.
Harris also reminded the audience of the horrific photos of war crimes from Bucha, civilians killed in a theater in Mariupol, a woman in labor who was killed by a missile attack, a UN-confirmed case of a four-year-old girl who suffered a sexual assault by a Russian soldier, and other
"First, from the starting days of this unprovoked war, we have witnessed Russian forces engage in horrendous atrocities and war crimes. Their actions are an attack on shared values and our common humanity," Harris said
In particular, she noted that Russian forces are conducting large-scale and systematic attacks on civilians – "gruesome acts of murder, torture, rape, and deportation."
"Execution-style killings, beatings, and electrocution. Russian authorities have forcibly deported hundreds of thousands of people, from Ukraine to Russia, including children. They have cruelly separated children from their families," she said.
On February 8, it was reported that US Vice President Kamala Harris would arrive in Munich to take part in a security conference. The visit will take place from February 17 to 19.
On February 18, Finnish Prime Minister Sanna Marin said that the West's sluggish reaction to the occupation of Crimea had pushed Russian President Vladimir Putin to a full-scale war against Ukraine.