The two who were arrested on Tuesday sat for their paper in the Kilimani police cells after a court allowed police to detain them there while conducting further investigations into the attack.
A third student is at large and efforts to trace him are ongoing.
Police said the three had attacked a pedestrian on November 4 in Jamhuri area and robbed him of his shoes, laptop, mobile phone, assorted clothes and a perfume.
On November 8 one suspect identified as Joseph Kimathi alias Garang was arrested while wearing the rubber shoes that were robbed from the victim.
Two other accomplices who were trying to have the laptop and mobile phone formatted were arrested at a shop in Kilimani area.
They later confessed to police who went to a house of one Kelvin Mwangi where the students were found.
Police say two home made guns capable of firing ammunition, the stolen mobile phone and the perfume were recovered.
Four rolls of bhang were also recovered from the house in Kibera.