A BBC radio correspondent was detained in Tajikistan for alleged membership in an extremist Muslim organization, police said Wednesday.
Police spokesman Makhmadullo Asadulloyev said 50-year-old Urunboi Usmonov is suspected of being a member of Islamic movement Hizb-ut-Tahrir, which is illegal in the Central Asian republic.
The BBC World Service, however, rejected suggestions that Usmonov had any links to Hizb-ut-Tahrir and demanded that Tajik authorities release him with immediate effect.
According to police, Usmonov, a citizen of Tajikistan, joined the banned group in 2009 to carry out "propaganda and promoting this movement in social networks."
The BBC said the charges are unfounded and that Usmonov has been denied access to legal representation.
Despite its designation as an extremist group, Hizb-ut-Tahrir has publicly foresworn the use of violence. It is an international pan-Islamic organization that operates legally in many countries, including Britain.
Tajikistan holds strategic importance in the NATO military campaign in Afghanistan, serving as a link in supply routes.
As the impoverished former Soviet republic fights a strong Islamic insurgency at the Afghan border, authorities led by long-time President Emomali Rakhmon have maintained a tight grip over the media and civil rights groups.
Usmonov, who works for the BBC World Service's Uzbek language service, has been kept in a high-security prison in Tajikistan's north for two days, although the court only sanctioned his arrest Wednesday afternoon, the journalist's lawyer, Fayzinisso Vakhidova, told the Associated Press.
Vakhidova said Usmonov had been denied access to legal help for two days, adding that he is accused of using his job to promote the organization's ideas.
The BBC said Usmonov's family told them he went missing on June 13, and returned home one day later accompanied by Tajik security service officials.
Family members reported that he appeared to have been beaten up, the broadcaster said in a statement.
Tajik authorities have conducted a vigorous campaign to quash Islamic movements not under some degree of control by the government. The arrest of devotees belonging to Hizb-ut-Tahrir and similar groups are frequent and prison sentences tend to be severe.