Police said the patients overpowered guards and escaped Sunday from Mathari Mental Hospital, after complaining that the pharmaceuticals given to them weren't working as they should, The Standard reported.
Mathari is the largest psychiatric hospital in Kenya.
Senior Nairobi police officer Moses Ombati told the BBC the patients were protesting before overpowering guards and fleeing.
"We have all their [the patients'] particulars, including their pictures and that will make it easy for us to identify them," divisional police chief Samuel Anampiu told the Standard.
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