On Sunday, police said a local man had been arrested and later sectioned under the Mental Health Act.
In a statement, Lancashire police said: Police have been making a number of inquiries throughout the weekend and have this afternoon arrested a man in connection with the investigation.
Man arrested for racist graffiti attacks on Lancashire mosque
A 47-year-old-man from Preston has been arrested on suspicion of racially aggravated criminal damage. He has since been assessed and sectioned under the Mental Health Act.
The first offence took place outside the mosque some time overnight between Thursday and Friday. A hate crime investigation was launched and the writing was removed from the gatepost, but a second report of graffiti in the same location was made to police on Saturday at 10.45pm.
At 6.15am on Sunday, a further report was made that more offensive writing had been added to the gatepost.
Read more On Friday, the mosques official Twitter account posted a photograph of the words scrawled at the site entrance, alongside a photograph after it was cleaned up. An accompanying message read: Before and after … all cleaned up in readiness for the main Friday prayers.
Officers have been making a number of enquiries throughout the weekend and have this afternoon arrested a man in connection with the investigation.
Lancashire Police said: “A 47 year old man from Preston has been arrested on suspicion of racially aggravated criminal damage.
The police investigation followed an initial report of hate crime on Friday April 19 when graffiti of a racist nature was found on the mosque in the same place.
Chief Inspector Gary Crowe of Preston Police, said earlier: “I would like to reassure people, especially worshippers in the area, that we are taking this extremely seriously.
“This is completely unacceptable, hateful vandalism and this kind of behaviour will not be tolerated.
“We are working to get the most recent graffiti removed as quickly as possible and would like to thank the community for their support with our investigation so far.
“We will continue to maintain a presence in the area and are following up on forensic and CCTV enquiries.