A Russian-led security group says it has not ruled out military intervention to quell the unrest in southern Kyrgyzstan.
The Collective Security Treaty Organization (CSTO) held an emergency meeting in Moscow Monday to discuss a response to the situation.
Russian media quoted CSTO Secretary General Nikolay Bordyuzha as saying the organization has everything it needs to act in such situations, including a peacekeeping contingent and collective rapid deployment forces of the Central Asian region.
Russia has sent paratroopers to protect its airbase in the country, but has so far rejected interim President Rosa Otunbayeva's request that Moscow send peacekeeping troops.
The United States also has an airbase in Kyrgyzstan, which is key to military operations in Afghanistan.
Both Russia and the U.S. have pledged humanitarian assistance, with a U.S. State Department spokesman, P.J. Crowley on Monday calling for a coordinated international response to the crisis.
The U.S. embassy in Kyrgyzstan said Monday the U.S. government has committed more than $800,000 for immediate humanitarian aid. The embassy also said it has identified $200,000 in medical and emergency supplies that it is working to distribute.
The Organization for Security and Cooperation in Europe, currently chaired by Kyrgyzstan's neighbor, Kazakhstan, has sent a special envoy to the country. The OSCE was also holding an emergency meeting Monday to determine an international response.
And in New York, the United Nations Security Council was to be briefed on the crisis in a closed meeting later on Thursday.
The U.N. High Commissioner for Human Rights, Navi Pillay, expressed alarm at the escalating violence and urged Kyrgyz authorities to take swift action to protect citizens, "irrespective of their ethnic origin."
Pillay released a statement Monday saying indiscriminate killings and rapes, including of children, appear to have been taking place on the basis of ethnicity.
Some information for this report was provided by AFP.