Four men have been arrested in the investigation into the murder of journalist Lyra McKee in Londonderry.
The men, who are aged 20, 27, 29 and 52, were arrested in Derry under the Terrorism Act on Tuesday morning.
They are being questioned by detectives at Musgrave Serious Crime Suite in Belfast.
Ms McKee, 29, was shot dead while observing disorder in Derry on April 18 2019.
Following the arrests, the Senior Investigating Officer, Detective Superintendent Jason Murphy renewed his call for the public to help him bring Lyra’s killers to justice.
He said he always believed that "some people within the community know what happened and who was involved".
He added: "I understand that people may be frightened to talk to us. I have previously given my personal assurance relating to anonymity for the purpose of this investigation and I renew this assurance today, as we approach the anniversary of Lyra’s murder.
"I want the community in Creggan to think about how that horrific attack impacted them personally and how it impacted the entire community. We saw widescale revulsion after Lyra was murdered and I remain determined to work with the community and local policing to convert that revulsion into tangible evidence to bring those who murdered Lyra to justice.
“I also know that many people were recording mobile phone video clips that night and whilst we had a huge response to my initial appeal for those videos, I believe that others may exist. I would ask anyone who has mobile phone footage to upload it onto our Major Incident Public Portal at www.MIPP.police.uk.”
PSNI Chief Constable Simon Byrne welcomed the arrests.
In a tweet, he said detectives are “working hard in the pursuit of justice”, adding that “anyone with information should come forward to police”.
