Alisher Iminzhanov, a Kyrgyzstani leader of the outcast group Hizb-ut-Tahrir, was detained in Osh on July 17th.  His arrest has been cast as a preventive measure for the festivities associated with the annual summer SCO summit, which starts on August 16th.  Kyrgyzstan believes that at least 5,000 supporters of HuT within its borders.

What is Hizb ut-Tahrir?
Hizb-ut-Tahrir (Party of Liberation) is an Islamic religious group that believes in the eventuality of a new Caliphate.  The movement was founded in 1953 by a Sufi Islam scholar, Taqiuddin al-Nabhani.  According to Wikipedia:

Hizb ut-Tahrir has set out a three-stage plan of action to achieve its goals:

1. Establish a community of HuT members who work together in the same way as the companions of Muhammad. Members should accept the goals and methods of the organization as their own and be ready to work to fulfill these goals.
2. Build public opinion among the Muslim masses for the caliphate and the other Islamic concepts that will lead to a revival of Islamic thought.
3. Once public opinion is achieved in a target Muslim country through debate and persuasion, the group hopes to obtain support from army generals, leaders, and other influential figures or bodies to facilitate the change of the government. The government would be replaced by one that implements Islam “generally and comprehensively”, carrying Islamic thought to people throughout the world.
[See HuT pamphlet]

A less sympathetic description of HuT plan by Dosym Satpayev, director of a Kazakh think tank Assessment Risks Group, is that HuT

“plans its development in three stages… First they convert new members. Secondly, they establish a network of secret cells, and finally, they try to infiltrate the government to work to legalize their party and its aims.”

Like everything about Hizb-ut-Tahrir, this Wikipedia article is disputed.

New constituencies and converts
A recent RFE/RL article documents the rise of women in the HuT organization.  Seven women were all charged and arrested in Uzbekistan, which frequently uses Islamic extremism as a legitimizer for arrests.  However, the article documents other indicators of women's participation across Central Asia–handing out leaflets, for instance–and the reasons why women are becoming participants.  The reasons continue to be those associated with a low economic opportunity, and political repression is giving opportunities for it to flourish in realms beyond examination.

Families that have lost their male head of household due to economic migration, religious persecution, or imprisonment for Hizb-ut-Tahrir activities frequently turn to the organization for assistance.  Leaflet distribution, for instance, is apparently a somewhat paid activity and probably helps a destitute family gain a social services network.  This article points out that recruitment (or conversion) tends to spread within prisons as well.  Those Hizb-ut-Tahrir members who are on the run against the law find themselves in association with others of dubious legal status.  For me, the problems with prosecuting Hizb-ut-Tahrir tends to rest in these problems of association.

Reading the language of reports
Last of all, since Hizb-ut-Tahrir advocates a people's transformation of faith and conversion, eventually, of state leaders toward a Caliphate, news that discusses Hizb-ut-Tahrir's  ”calls to overthrow” the government can be a bit misleading.  In their tracts and in their acts–no violence has been asked for or committed.  Indeed, the State Department watches HuT pretty carefully but does not call it a terrorist organization.  However, as I noted before, it is difficult to follow its “cell” character.  The Russian Federation, Kazakhstan, Kyrgyzstan, Tajikistan, and Uzbekistan have all banned it; other states are seriously considering such a ban, including Great Britain.

For the SCO meeting, other religious groups are also being targeted by Kyrgyztan's security services, including: Falun Gong, Rev. Sun Myung Moon's Church, Maharishi Mahesh Yogi's TM movement. 

Further Reading:
Tajikistan arrests 99 HuT members in 2005–RFE/RL, January 2006
Wikipedia on Hizb-ut-Tahrir
Global Security on Hizb-ut-Tahrir
Forum 18–an NGO devoted to religious freedom in blogroll at right