Photo: EPA-EFE/MAXIM SHIPENKOV

Tajikistan’s State Committee for National Security has detained nine people suspected of having ties to the perpetrators of last Friday’s terror attack at a concert hall near Moscow, Reuters and state news agency RIA Novosti wrote Friday.

All nine suspects were detained in the city of Vahdat in western Tajikistan on Monday, according to Reuters, and then transferred to the capital, Dushanbe. The country’s special services suspect the detainees may have ties to Islamic State.

Eight suspects have so far been remanded in custody in Russia on terrorism-related charges following the concert hall attack that killed at least 144 people and injured hundreds more.

The four suspected gunmen were named by the court on Sunday as Dalerdzhon Mirzoyev, Saidakrami Murodali Rachabalizoda, Muhammadsobir Fayzov and Shamsidin Fariduni. All four are citizens of Tajikistan.

Dilovar Islomov, the last owner of the car allegedly used by the suspected attackers to reach the concert venue, was placed in pre-trial detention on Monday, along with his brother Aminchon and father Isroil. Isroil Islomov is a Tajik citizen with a Russian residence permit, while his sons hold Russian citizenship.

The last suspect to have been remanded in custody so far is Alisher Kasimov, a Russian citizen born in Kyrgyzstan, who is believed to have rented an apartment to the attackers.