Detectives are investigating how eight of the nine suspects disappeared Wednesday night from the Thika police station under a tight security.
The suspects Livingstone Njau, Francis Matheri, Allan Mugai, Charles Mitaru, John Murege, Eric Ngigi, Arthur Kayemba and Bunton Mbugua, escaped at around 4pm.
However the ninth suspect Joseph Nyaguthii was arrested by traffic police officers 500 meters from the station, while his colleagues managed to escape.
The DCI detectives are trying to determine how the suspected robbers left the facility despite tight security.
It is alleged that the incident took place after one of the suspects pretended to have health problems that he was having diarrhea.
According to the patrol officer, his fellow suspects asked to be escorted to the toilet, but they had a conspiracy to disappear.
The suspects, who were facing charges of robbery with violence, were detained at the Thika police station after being brought there from the main industrial area, awaiting trial.
Meanwhile, the officer who was attacked by the suspects as they were escaping is currently being held at the police center while assisting detectives in their investigations.