Thirty-eight Kenya Revenue Authority employees who were locked up for 14 days have filed an application at the High Court challenging their detention.
On Monday, a court had ruled that the KRA staff remain in custody for two weeks as detectives probe a tax evasion scandal.
Another 30 workers have also been arraigned with police seeking to have them detained for 21 days.
Four other suspects who were summoned at the Directorate of Criminal Investigations for questioning are seeking anticipatory bail ahead of their prosecution.
Last Friday, 70 KRA staff were arrested but only 38 appeared were arraigned before Senior Resident Magistrate Paul Mayova.