A journalist has been shot dead during rioting in Londonderry that police are treating as a "terrorist incident".
Dissident republicans are being blamed for killing 29-year-old Lyra McKee during rioting after police searches in Derry's Creggan area on Thursday night.
The Police Service of Northern Ireland (PSNI) said the New IRA "are likely to be the ones behind this" and detectives have started a murder inquiry.
Prime Minister Theresa May said the murder was "shocking and senseless".
Ms McKee was a journalist who "died doing her job with great courage", added Mrs May.
The PSNI said that a gunman fired shots towards police officers at about 23:00 BST on Thursday.
Mobile phone footage taken by a bystander during Thursday night's rioting appears to show a masked gunman crouching down on the street and opening fire with a handgun.
Ms McKee, who was standing near a police 4x4 vehicle, was wounded.
"She was taken away from the scene in a police Land Rover to Altnagelvin Hospital but unfortunately she has died," said Assistant Chief Constable Hamilton.
The leaders of Northern Ireland six biggest political parties said they were "united in rejecting those responsible for this heinous crime".
In a joint statement, they said: "Lyra's murder was also an attack on all the people of this community, an attack on the peace and democratic processes.
"It was a pointless and futile act to destroy the progress made over the last 20 years, which has the overwhelming support of people everywhere."The National Union of Journalists (NUJ) said Ms McKee was "one of the most promising journalists" in Northern Ireland.
She was a journalist of "courage, style and integrity" and a "woman of great commitment and passion", said the union's Séamus Dooley.
"I have no doubt that it was that commitment which led to her presence on the streets of the Creggan last night, observing a riot situation in the city."
Taoiseach (Irish Prime Minister) Leo Varadkar said: "Our solidarity also goes out to the people of Derry and to the entire journalism community.
"We cannot allow those who want to propagate violence, fear and hate to drag us back to the past."