It is possible that the Hizb ut Tahrir has contacts with other groups, maybe it has infiltrated in them, but in my opinion, it is not a centralized organization; it uses different methods in different places. Anyway, they are far from being extremists that incite holy war and murder. In Uzbekistan, average Muslims are often looked upon as if they were members of the Hizb ut Tahrir. It is very difficult to know who the extremists are and who commits the crimes. In the region there are many small unknown organizations about which we can only suppose are linked to the Hizb ut Tahrir.
The caliphate already existed in the history of Islam. Today many understand that it is impossible to return to that old version of the caliphate, when Islam embraced immense regions. That idea of the caliphate is in contradiction with national Islamic ideologies and of many other types. I believe that the return to that dream of the caliphate is a reaction to “religious ideologization” caused by modernization. We might wonder who the caliph would be.
Except for some exceptions, Islamic countries are directed by authoritarian regimens of left or right. People who suffer from these types of governments see their salvation in religion. After the Iranian revolution, the Islamic countries have felt fear and have tried to foment an official Islam that allows them to control it. This, as well as “islamization” has become a political force. The only means of fighting against it consists of making an opening in the political system. In that sense, the example of Erdogan it is significant in that it shows the road traveled by the leader of an Islamic party to the position of prime minister. Thanks to the role that he has carried out, today we are looking at the possibility that his country, now modernized, can join the European Union.

Source
Gazeta SNG (Russia)
Gazeta SNG is an online news daily in Russian language.

" В Узбекистане обычных мусульман часто принимают за экстремистов ", by Shirin Hunter, Gazeta, May 13, 2005. Text adapted from an interview.