South Wales Police have arrested a 21-year-old man on suspicion of criminal damage and assault after an incident at a Neath mosque in the early hours of Friday morning.
A number of windows on the building were smashed, and a 44-year-old woman and a 48-year-old man were assaulted.
The man, who police say lives locally, remains in custody while an investigation is carried out.
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A colder day than yesterday, especially in the east. Remaining cloudy with some patchy light rain and drizzle, mainly over higher ground.
The party groups decide their positions for this afternoon's crucial vote on whether to support the Wales Bill.
Theresa May is to give details of Brexit plans in a speech in which she will say she does not want the UK "half-in, half-out" of the EU.