A further four people have been arrested over what police have termed a “significant” gathering in east Belfast last month.
Three men, aged 35, 39 and 40, and a 32-year-old woman were arrested on suspicion of terrorism and other related offences on Wednesday.
A number of searches were conducted in east Belfast, Dundonald and Newtownards on the same day.
A total of 15 arrests have been made in the police probe into the gathering at Pitt Park on February 2 and activities linked to the east Belfast UVF.
Detective Chief Superintendent John McVea said the investigation remains ongoing.
“I would continue to appeal to anyone in the community who has information or footage regarding the incident, or criminality in the area, to contact the police,” he said.