Located in the heart of the tense Central Asia region and sharing a border with Afghanistan, Tajikistan has battled with radical Muslim groups for years, including Hizbi Tahrir, which is banned for its plans to set up a radical Muslim state in Central Asia.
Radical Islamists, most of them aged between 18 and 40, have grown markedly bolder in preaching the party's ideology without fear of arrest, distributing leaflets in markets, colleges and hospitals, authorities say.
"In 2003 Tajik police arrested over 70 members and mid-level leaders of Hizbi Tahrir, which is a jump on last year," one interior ministry official said.
Authorities also seized loads of leaflets calling for the government's overthrow and arrested two underground publishing houses in the country's north and the capital Dushanbe.
"The party profits from people's poverty, while getting funds from non-governmental Arab and Islamic foundations," said political analyst Abdugani Mamadazimov.
In the last four years, more than 400 members of Hizbi Tahrir have been arrested in this former Soviet republic, 130 of them sentenced to varying prison terms.
If convicted, Hizbi Tahrir activists face up to 18 years in jail for "inciting racial and religious hatred and calling for a forceful overthrow of the constitutional order."
Founded in 1950 in the Middle East, Hizbi Tahrir appeared in Uzbekistan's eastern region of Fergana a decade ago before spreading into Tajikistan and Kyrgyzstan.
However, Tajikistan's Islamic opposition movement, which took up arms during the civil war that tore the country apart from 1992 to 1997 and cost some 150,000 lives, dismissed Hizbi Tahrir's ideas as hopeless.
"Hizbi Tahrir's call for an international Khalifat (Islamic state) is pure utopia," spokesman for the Islamic Party of Tajikistan's Rebirth, Khikmatullo Saifullozoda, said.
The Islamic Rebirth Party, which numbers some 40,000 members, considers the Hizbi Tahrir ideology alien to Central Asia and Islam as a whole, Saifullozoda said.
However, "Hizbi Tahrir found support among the ethnic Uzbeks, and extremists may become so strong that they will hinder the normal political balance," he warned.
Hizbi Tahrir numbers up to 5,000 members, and its influence is slowly shifting from the mountainous Sogd region in the north to the populous south, officials said.
Tajikistan's 6.3-million population is 95 percent Muslim.