Protesters clashed with police as they gathered in a city for a planned demonstration linked to the Southport knife attack.
Stones and beer cans were thrown at police in riot gear outside a mosque in Sunderland.
Mounted officers pushed back demonstrators, some of whom were in masks, from the mosque on St Mark’s Road.
Northumbria Police said it advised members of the public to avoid the area.
The unrest follows riots in Hartlepool on Wednesday night, which Cleveland Police said was linked to protests over the fatal knife attack on a group of children in Southport, Merseyside, on Monday.
A crowd of about 200 anti-racist protesters also gathered outside the Abdullah Quilliam Mosque in Liverpool after rumours of a far-right protest there.