PORTADOWN, Northern Ireland (Reuters) -Rioters attacked police with petrol bombs, rocks and fireworks in the Northern Irish town of Portadown on Thursday, a Reuters witness said, as a fourth night of anti-immigrant violence moved to a different part of the British-run province.

Police have come under attack for a fifth consecutive night in Northern Ireland, in what has been dubbed a ‘week of shame’ for the region.

Police say 41 officers have been injured and 13 people have been arrested after three nights of rioting across several towns.