Migori Governor Okoth Obado will spend another night in police cells, following his arrest over possession of items including eight firearms.
Kibera Chief Magistrate Joyce Gandani made the ruling on Thursday, when the governor appeared before her.
Ms Gandani said the governor will spend the second night at Gigiri police station and return to court on Friday for a ruling on his release.
Mr Obado was arrested on Wednesday after Ethics and Anti-Corruption Commission (EACC) detectives raided his homes and office and found items including eight guns.
His lawyers said he spent the night at Gigiri Police Station.
The prosecution wants Mr Obado held for 15 days for proper investigations into the guns case.
The EACC is also looking into claims that Mr Obado used proxies, among them his relatives, to siphon Sh2 billion from the coffers of the county government.
This is according to an affidavit filed in court by the anti-corruption watchdog.
The county boss is also facing murder charges in the case of Rongo University student Sharon Otieno, who was his girlfriend.
In the case of Ms Otieno, he was freed on a cash bail of Sh5 million under strict conditions that include staying at least 20km away from Homa Bay, which is Ms Otieno’s home county.