Kenyan police raided Mombasa's Musa mosque on February 2, detaining scores of suspects whom they accused of attending a radicalisation meeting. The raid sparked riots in Mombasa in which three people received stab wounds.
"The suspects were arrested as they planned to perform a terrorist act," prosecutor Onesmus Towett told the court.
"If released on bond or bail they will further an act of terrorism and there is (an) intelligence report which indicated they were plotting to execute an act of terrorism on unspecified and specified targets," he added.
The 70 denied all the charges, and the court is set to make its ruling on whether bail will be allowed on February 26, 2014.
Security was tight around the court as hundreds of families and relatives jammed the premises to hear the proceedings.