Five suspects, including a Canadian citizen, appeared in a Kenyan court on Friday in connection with an Islamist attack on a Nairobi hotel complex that left 21 dead.
A magistrate granted a request from the prosecution to detain the four men and one woman for 30 days while investigations continue.
The suspects are accused of "possible involvement in the almost 20-hour siege of the DusitD2 hotel and office complex by a suicide bomber and four gunmen who were all killed by security forces, a court document said.
"The investigations into this matter are complex and transnational and would therefore require sufficient time and resources to uncover the entire criminal syndicate," a statement from Director of Public Prosecutions Noordin Haji said.
A total of 11 suspects were arrested after Tuesday's attack, however investigations into the others were still ongoing.
Those who appeared in court include Joel Ng'ang'a Wainaina, a taxi driver who ferried the attackers around on several occasions, and Oliver Kanyango Muthee, a taxi driver who drove one of the assailants to the scene of the attack.
Gladys Kaari Justus is being investigated over the transfer of money while Guleid Abdihakim -- who holds Canadian citizenship -- is being probed over suspicious communication.
The other suspect Osman Ibrahim is alleged to have met with one of the attackers on January 8.
Two suspects yet to appear in court, Ali Salim Gichunge and Violet Kemunto Omwoyo possessed SIM cards that were in "constant communication" with numbers in Somalia, court documents revealed.
The attack was claimed by Somali Islamist group Al-Shabaab, an affiliate of Al-Qaeda which has repeatedly targeted Kenya over the presence of its troops in Somalia.
In 2013 an attack on the Westgate mall in Nairobi left 67 dead, while in 2015 Shabaab killed 148 people at a university in Garissa, eastern Kenya.