Kileleshwa Member of County Assembly Elias Otieno is expected in court on Friday to face assault charges after he allegedly assaulted Kayole South MCA Elizabeth Manyala at City Hall.
Otieno spent the night at Central Police Station after he was arrested at 5pm on Thursday for the alleged assault.
He was arrested at a restaurant in town while he was in the company of two people.
Ms Manyala was admitted to Nairobi Hospital after the incident, which occurred last week on Wednesday.
She alleged that Otieno, who is also the Majority Leader at the Nairobi County Assembly, slapped her several times and pushed her to the wall.