The cleaner was reportedly in the church kitchen when he suddenly snatched a knife and starting swinging it around while chasing people.
The cleaner was seen wielding the knife while pursuing persons in the church from the inside of the building to the open air carpark.
The incident took place at around 10am.
At the time, children were studying in the kindergarten on the church compound.
Frightened parents who spotted the frenetic cleaner quickly called the police while teachers shut the classroom doors.
Police officers subsequently managed to subdue the cleaner and arrest him.
The 3 persons who were injured were sent to hospital.
The church says the cleaner was working for a cleaning company which the church had contracted.
The reason for the cleaner’s violent and unexpected outburst are unclear.
Police are investigating the incident.