The taxi driver linked to the murder of Mildred Odira, a woman who worked as a switchboard operator at the Nation Media Group, has been released.
Senior state counsel Christine Mbevi informed Kiambu Chief magistrate Patricia Gichohi that police have no sufficient evidence to charge David Junga Ochieng with murder.
He was the only suspect in the murder case.
During Wednesday's mention of the case, Ms Mbevi told the court that police will now treat Mr Ochieng as a possible prosecution witness.
The magistrate allowed the prosecution to close the investigation file against Mr Ochieng and a cash bail of Sh 200,000 deposited at the court be refunded to him.
Mildred Odira was last seen leaving her home in Kariobangi South on January 29 heading to the hospital.
Security guards at her resident called a taxi to take her to Ruaraka's Uhai Neema Hospital after she fell ill that night. According to Mr Ochieng, he dropped Mildred at the hospital and left.