The United Nations and European Union both urged an independent probe, a call that was echoed in Washington by visiting British Foreign Secretary Jack Straw.
"I call now for an independent international inquiry to find out why the killings happened, the nature of the killings, and who was responsible. That means a credible and transparent investigation with, for example, the involvement of appropriate international bodies," Straw said.
While it's unclear what form such an investigation would take, Straw said it "must have credibility in the eyes both of the international community and of the Uzbek people."
The Uzbek government says 169 people were killed in Andijon in battles with Islamic radicals on 13 May after gunmen raided government installations and overran a prison, releasing inmates. Opposition activists say at least 745 people, most of them civilians, were killed -- more than 500 in Andijon and about 200 in nearby Pakhtaobod.
Much of the international community has condemned the crackdown. But officials in neighboring Tajikistan and Kyrgyzstan have said that Uzbek officials acted prudently to put down a riot that could have sparked much wider bloodshed.
Sonya Sceats is with Chatham House, a London policy institute. A human rights lawyer specialized in international criminal justice, Sceats told RFE/RL that the United Nations is likely to be at the heart of any inquiry into the alleged atrocities.
"I would imagine that some kind of functionary associated with the commission on human rights would be organized, probably under the direction of Louise Arbor, who is the current UN commissioner for human rights," Sceats said. "They may create also a special position of a special rapporteur who may be sent over to Uzbekistan to investigate the atrocities."
Sceats says that investigation would entail interviewing witnesses and residents as well as government and military officials. "I think the weight would be significant," she said. "The United Nations doesn't send those sorts of functionaries in there at a whim. And obviously, there are all kinds of implications. The United Nations General Assembly might sort of jump on the issue. I think there would be a lot of implications in terms of international relations."
But it remains unclear just what kind of leverage the international community could bring to bear on Uzbekistan, whose regime thrives in relative political and economic isolation.
For now, a shift in rhetoric has been heard in Washington, which has an air base in Uzbekistan and considers the country a key ally in the war on terrorism. U.S. Secretary of State Condoleezza Rice urged Tashkent this week to respond to the widespread discontent in society by opening up and embracing reforms.
Filip Noubel, the program manager on Central Asia for the London-based Institute for War and Peace Reporting, told RFE/RL that an international inquiry could actually help the Uzbek government to realize that it needs to open up precisely to avoid a similar crisis elsewhere in the country.
"It's been years since President Karimov has promised to deliver on a number of issues -- on economic reforms, on more freedoms, on a more civic society able to develop in Uzbekistan. And this has not happened and this is exactly why we have this situation today. So one way to start would be for the international community, through this investigation, to assess this reality in the country and to realize that there has to be immediate reforms and this cannot be delayed, because as I said, we will see the same violence go on in other places in the Ferghana Valley," Noubel said.
Uzbekistan since the collapse of the Soviet Union has seen economic decline and hard-line autocratic rule, with thousands of religious and political opponents behind bars.
Residents and a local human rights activist say the Andijon rebellion was staged by locals protesting poverty, corruption, and Karimov's tough line on Muslims.
A sampling of that discontent was heard yesterday on RFE/RL's Kyrgyz Service, which interviewed an Uzbek refugee identified only as Bobur who had fled the violence in Andijon.
"I got a bullet wound [in the shoulder] when I was on the street [in front of regional-administration building on 13 May]," he said. "They [Uzbek authorities] closed our companies, big companies. We were entrepreneurs. They closed our companies saying we were supporting [Islamic extremists]. We denied it, but they closed our companies anyway. The trial lasted for three months. People became [jobless] because those companies provided a lot of jobs."
But what if Uzbek authorities fail to heed the calls for greater openness and change? Noubel says there are also other levers of possible influence, such as financial pressure that could come from institutions that assist Uzbekistan, such as the European Bank for Development and Reconstruction (EBRD).
"The EBRD has, I think, been one of the most courageous financial institutions in this regard and they have always conditioned their help to basic requirements in human rights, in democratization in both Uzbekistan and Turkmenistan, actually. In some cases, they have suspended their programs because benchmarks were not met. This, of course, should be expanded. The most important thing is the West has realized that this regime is not sustainable and we all have to think of a different way to rule that country," Noubel said.
Yesterday, the EBRD said it might leave Uzbekistan altogether and the International Monetary Fund said the unrest would have a negative impact on the country's economy.
Meanwhile, human rights lawyer Sceats says that depending on the severity its findings, an international probe could eventually lead to call for Uzbek officials to face trial for crimes against humanity, perhaps at the new International Criminal Court at The Hague.
Noubel says the fact that Uzbek authorities have given even a limited tour of Andijon to diplomats is a sign that they are at least somewhat concerned with their global image.
But the specter of unrest still looms. Troops today moved into the border town of Karasu. No clashes were reported, but witnesses say there were arrests, including of the alleged Andijon protest leaders.
[For more on these events, see RFE/RL's dedicated webpage: Unrest in Uzbekistan]
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