Also caught in the net are scores of independent human rights activists and journalists who have covered last month's bloody events in Andijon in international media outlets.
Tulqin Qoraev, who works for the London-based Institute for War and Peace Reporting (IWPR) and has contributed to Radio Iran's Uzbek programs, was among the latest to be detained. Qoraev, who freelanced in the past for RFE/RL, was arrested on 4 June in his hometown Qarshi in southern Uzbekistan.
Relatives told RFE/RL's Uzbek Service that officers brought Qoraev before a judge, who charged him with hooliganism.
"He was detained by the Interior Ministry officers and charged at the city court," said Qoraev's brother. They used a woman for this slander, for this provocation. He is charged with hooliganism under Article 183 (of the Uzbek Criminal Code). I don't know about other charges."
The independent Human Rights Society of Uzbekistan (HRSU) reported that a woman at a bus stop attacked Qoraev and a friend of his and later filed a suit against the reporter.
The HRSU also says its members are being harassed.
Norboy Kholjigitov, the HRSU's Samarqand-based activist, was also detained on 4 June. Kholjigitov's son, Hayotilla, told RFE/RL about his father's arrest.
"On June 4, at around 11-12 p.m., Uktam Kholnazarov, a community leader, came to our house. He and my father, Norboy Kholjigitov, left for a nearby village," Hayotilla said. "My father was in a local teahouse where he was handcuffed and detained by the SNB (security service) officers. I was told those people were from the SNB. Abdusattor Erzaev, a teacher from the local school, was also detained that night."
Relatives said they had no information about Kholjigitov's whereabouts. Abdijalil Boymatov of the HRSU says he believes the arrest is part of a government campaign to silence critics.
"He (Kholjigitov) is a farmer himself, he's defended farmers' rights, he participated in many protests, went to Tashkent to organize demonstrations," Boymatov said. "He has confronted the government on many occasions."
Other rights groups as well as opposition parties have also become the subject of harassment and persecution.
Last week, an Andijon-based member of Ezgulik group, Muzzaffarmirzo Iskhakov, and two members of the unregistered opposition party Birlik, Akbar Oripov and Nurmuhammad Azizov, were detained and had their apartments searched and computers and documentation confiscated.
Similar cases have been reported in the central city of Jizzakh. Bakhtiyor Hamraev, a human rights activist, says the whereabouts of several of his colleagues are unknown.
"In Jizzakh, human rights activists have started to disappear," Hamraev said. "For example, Rajab Nazarov went missing. We don't know where he is. I think the government is using the ultimate means of getting rid of human rights activists -- it is physically eliminating them."
So far there is no evidence that any of those who have gone missing have suffered serious harm.
Many other rights activists say they are being constantly watched and followed by security service officers.
"The situation is the same today, too," said Tashkent-based rights activist Surat Ikramov. "They asked me not to leave my house. They told me, 'If you have to leave the house and go somewhere, we will follow you.'"
The HRSU's Boymatov says he, too, was not allowed to leave his home.
"I was unable to leave my house for almost 15 days," Boymatov said. "From 22 May to 3 June, there were five or six [policemen] from the Interior Ministry's Khamza district department near my house. They didn't let me go out."
Estimates by rights groups of the number of people detained since the Andijon events have ranged from scores to as many as 100.
They say that not only journalists and rights campaigners but also politically active citizens who protested against the government policy have become a subject of harassment. Abduvohid Tohtahojaev from Tashkent is one of them.
"Three policemen came to my house at 4:30 in the morning," Tohtahojaev said. "They rang the bell, banged on the door, and woke up all my neighbors. They wanted to force me to go with them. My neighbors came out. My wife has high blood pressure. She had a stroke that morning. I refused to go with the policemen. They detained my brother, my son and my nephew. They told me to stay at home. I asked why. They said they had an order."
Tokhtahojayev says he believes his participation in several demonstrations is the reason behind the policemen's visit and the detention of some of his relatives.
Tokhtahojayev and other protesters have repeatedly demanded that an independent investigation of the Andijon events be conducted, along with the release of human rights campaigners.
Uzbek President Islam Karimov has rejected such calls, which have also come from the United Nations, European Union, and United States.
(RFE/RL's Uzbek Service contributed to this report)
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