Between February 21 and April 2, police received reports of 26 offences of criminal damage across Milton Keynes.
The incidents involved graffiti at places of worship, the graffiti was of a racist nature in Willen, Broughton, Linford Wood and Kingston.
The graffit was daubed on grave stones and inside some church buildings. A memorial in Newport Pagnell was also targeted.
A 34-year-old man has been arrested in connection with the incidents and detained under the mental health act.
Milton Keynes neighbourhood inspector Michael Morland, said: “We are carrying out a thorough investigation in connection with this incident.
“We have arrested a man, but we are asking anyone with information or CCTV footage of any of these incidents to please come forward to assist in our investigation.