A 31-year-old man has been arrested in relation to a video that circulated on social media in June that appeared to show a group chanting about the murder of Michaela McAreavey.
The man was arrested on Wednesday and has since been released on bail pending further inquiries, police said.
It is understood that three males have volunteered themselves for a police interview in relation to the investigation.
This is the latest development in the fallout from the video. Apparently filmed in an Orange Hall in greater Belfast, it appeared to show several men singing a chant that mocked the death of Mrs McAreavey while on her honeymoon.
It prompted widespread condemnation across the political sphere in Northern Ireland and beyond.
The 27-year-old Co Tyrone teacher was strangled in her room at the Legends Hotel in Mauritius on January 10 2011.
Mrs McAreavey, who had married her husband John 10 days earlier, was attacked after she returned to her room alone and disturbed a burglary.
No-one has been convicted of murdering the daughter of Gaelic football manager Mickey Harte.
The Orange Order, which branded it “abhorrent”, has launched its own investigation into the incident.
In a statement published in June, three men who have apologised for their involvement said they would not be confirming or denying who had been interviewed by police, insisting that anyone subject to criminal investigation was entitled to privacy.
The men, who resigned from the Orange Order, reiterated their “complete shame and regret for their involvement in the incident”.
They insisted there was no intent to broadcast the chant on social media and it was “incidentally streamed” on Facebook Live.
“In any event, regardless of whether broadcast or not, the relevant behaviour is not acceptable in any section of our society either in public or private,” said the statement.
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