President Barack Obama condemned the violence in Yemen that killed at least 40 people Friday and injured hundreds, warning that those responsible will be held accountable.
Obama said in a statement that President Ali Abdullah Saleh should honor his pledge to allow peaceful demonstrations, adding that it was "more important than ever for all sides to participate in an open and transparent process that addresses the legitimate concerns of the Yemeni people."
Yemeni government snipers firing from rooftops and houses shot into a crowd of tens of thousands of demonstrators, who were demanding Saleh's ouster.
Obama said Yemen must advance in an orderly process toward greater democracy and prosperity.
His comments were echoed by Secretary of State Hillary Rodham Clinton, who declared herself "alarmed" by the violence against protesters. She said the U.S. was seeking to verify reports that the killings were committed by security forces.
Clinton called on Yemeni forces to refrain from violence, and said "a solution to Yemen's problems will not be found through security measures."