State Department spokesman Sean McCormack said Wednesday the department was compiling "any information that may indicate any crimes, any atrocities that may have been committed," but hadn't drawn conclusions yet.
Jendayi Frazer, assistant secretary for African Affairs, visited Kenya after violence erupted in the wake of President Mwai Kibaki's disputed re-election in December.
"There was ethnic cleansing in Kenya. I listened to the victims," Frazer told reporters in Addis Ababa, Ethiopia. "If they resisted, they were killed. That sounds like ethnic cleansing to me."
She later qualified her statements, saying they were based on what she was told by the victims, The Washington Times reported.
Frazer was "reflecting" her view of what was happening in the Rift Valley based on a visit several weeks earlier, McCormack said.
"I don't have anything to modify Jendayi's statement," he said.
When asked whether the Bush administration believed what happened in some instances constituted ethnic cleansing, McCormack responded: "Like I said, I don't have anything more to add to Jendayi's comments. I think they stand on their own."