Speaking on 14 May, one day after the bloodshed in Andijon, he said Uzbek authorities already had identified those involved as Islamists determined to overthrow the government.
"We have practically all the family names, and they are members of a current within Hizb ut-Tahrir that in Andijon is called Akramiya," Karimov said. "Their main purpose is to turn over the existing constitutional structure, to turn over the power in different places and found what is called a caliphate -- which would unite all Islamists. The movement was categorically against all sorts of constitutional institutions, against a secular development of the events. That is their purpose."
But many observers question Karimov's characterization of the events in Andijon as part of a longstanding confrontation between Tashkent and armed Islamist groups.
Daniel Kimmage, an RFE/RL regional analyst, says that no convincing evidence has yet been made public that proves Islamists organized events in Andijon.
"We know that the spark was provided by people who did take weapons in their hands and did attack a military garrison and a prison, so they were willing to engage in violence," Kimmage said. "That's a fact. But we don't have any convincing proof at this point that they were members of a Islamic radical organization. The ties between the businessmen who were on trial and known radical organizations are very tenuous, I haven't seen any convincing evidence that linked them to that."
The violence in Andijon on 13 May began with a group seizing arms from a garrison and then attacking a prison to release inmates -- including the 23 prominent local businessmen who were on trial on charges they belonged to the banned group Akramiya.
Several thousand other people massed in the central square around a seized building to protest against Karimov's political and economic policies.
An as-yet-uncertain number of people were killed by fire from security forces. The government says 30 died, including police. But witnesses and human rights groups put the number of civilian deaths as high as 500.
Olivier Roy, a regional expert with the Paris-based National Center for Scientific Research, told RFE/RL's Tajik Service that he also sees aspects of a grassroots movement in the events.
"I don't know about the real agenda of these groups," Roy said. "But it is clear that the demonstration has been waged by parents and families of the prisoners. So I think the first motivation of the people who went against the authorities was to free the prisoners. They did attack the jail. They didn't attack the government buildings first. So I think it is more some sort of a grassroots movement -- a protest from families of prisoners -- more than a really politically motivated movement."
RFE/RL's Kimmage says that if the Andijon protest was an expression of popular anger, it would be a major escalation of economically motivated protests in Uzbekistan in recent months.
"We have certainly seen several instances, even in the last year, where people have come out and they have protested primarily for economic reasons and this event that recently took place represents a quantum leap forward in that context, of course, with the qualifier that the spark here was over a specific incidence -- it was over a trial of people for alleged religious extremism," Kimmage said.
He notes that Andijon, the largest city in eastern Uzbekistan and located in the densely populated Ferghana Valley, is in a region that is experiencing worsening economic problems (click here for a map of the Ferghana Valley region).
Many there believe that Karimov's policy of preserving a highly centralized, command economy little changed from the Soviet-era concentrates power in government circles and generates too few new jobs.
Key questions now are whether the events in Andijon will be seen elsewhere in Uzbekistan as a popular movement or an Islamist-inspired rebellion -- and whether the government's use of force will discourage or spark further such protests.
Kimmage says that the crisis will further deepen debate inside and outside Uzbekistan over whether Karimov's government is protecting society from the threat of insurrection or -- by using such overwhelming force -- is adding to just that danger.
"His argument has always been that we face a threat that is so pressing and so perilous in Uzbekistan that we need the harshest measures to deal with it, whereas his critics have always said that it is precisely these harsh measures that radicalize people who otherwise would form a constructive opposition in the country. And this particular clash brings this conflict to a head," Kimmage said.
Adolat Najimova, the head of RFE/RL's Uzbek Service, says that despite that debate she sees little prospect Tashkent will change its policies toward those seen to challenge the government.
"Karimov basically doesn't have an exit strategy," Najimova said. "He is stuck, he is a victim of his own harsh policy and he might anticipate that the resentment of the Uzbek population toward him is pretty high. So, should he lose his power the implications could be unpredictable."
In Tashkent today, the prosecutors' office said a formal investigation has been launched into what it called the "murders and the organization of mass unrest" in Andijon.
The Interior Ministry announced that 70 people had been detained so far in connection with the 13 May violence in the city.
Click here for a gallery of images from the violence in eastern Uzbekistan on 13-14 May.
Bloody Friday In The Ferghana Valley
Uzbek President Blames Islamist Group For Unrest
Protesters Charge Officials With Using Extremism Charges To Target Entrepreneurs
Analysis: Economic Concerns Primary In Andijon
Background: Banned Hizb ut-Tahrir Faces Dwindling Appeal, Internal Divisions
Interview: Opposition Leader Tells RFE/RL About 'Farmers' Revolution'