The 29-year-old journalist shot and killed allegedly by dissident republican group the New IRA in Northern Ireland has been named.
Lyra McKee died after she was shot in the head as 'violent dissident republicans' fired on police in Derry in what is being treated as a "terrorist incident"
The investigative journalist, from Belfast, was at the scene as petrol bombs, bricks and bottles were hurled at police Land Rovers.
Eyewitnesses claimed a masked figure stopped at the bottom of the road and fired shots up towards where Ms McKee was standing.
People started to run for their lives, and Jake Hanrahan, a journalist who was at the scene, said Ms McKee was 'caught in crossfire'.
Police Service of Northern Ireland officers were carrying out a search operation in the Creggan area of Derry aimed at disrupting dissident republicans ahead of this weekend's commemoration of Irish independence, when a situation developed during which more than 50 petrol bombs were thrown at officers and two cars were hijacked and set on fire.
During the unrest a gunman fired a number of shots at police, Assistant Chief Constable Mark Hamilton said.
Speaking at a press conference at Strand Road PSNI station in Londonderry, Mr Hamilton said Ms McKee was murdered by dissident republicans.
He said: "Unfortunately, at 11pm last night, a gunman appeared and fired a number of shots towards police and a young woman, Lyra McKee, 29 years old, was wounded.
"She was taken away in a police landrover to Altnagelvin Hospital but unfortunately she has died there. We have now launched a murder inquiry here in the city.
"We believe this to be a terrorist act, we believe it has been carried out by violent dissident republicans, our assessment at this time is that the new IRA are most likely to be the ones behind this and that forms our primary line of inquiry."
"This is a horrendous act, it is unnecessary, it is uncalled for, it is totally unjustified."
There is no further information of the shooter as officers are still hunting for the suspect.
Ms McKee posted a picture of the riot on Twitter just minutes before her death captioned: "Derry tonight. Absolute madness."
It is understood award-winning Ms McKee had recently moved to Derry to live with her partner.
She worked as an editor for California-based news site Mediagazer, a trade publication covering the media industry, had been published by The Atlantic, BuzzFeed, Mosaic Science and others, and was working on a book which had been due to be published in 2020.
She had received a number of honours, including a Sky News Young Journalist Award, and was seen as a rising star in investigative journalism.
In 2016, Forbes Magazine named her one of their 30 under 30 in media. Her passion, as Forbes described, was to dig into topics that others do not care about.
Tributes have poured in for Ms McKee as friends and fellow journalists paid condolences.
One tribute read: "We were meant to have moved past this. I am sorry we failed you Lyra."
Another one said: "I can't believe it was you."
Matthew Hughes said he had been left "devastated" by the death of one of his closest friends.
"I just received the heartbreaking news that my friend @LyraMcKee was murdered tonight in a terrorist incident in Derry," he tweeted.
"She was one of my closest friends. She was my mentor. She was a groomswoman at my wedding. I can't imagine life without her, and yet now I must."
Ann Travers, whose sister Mary was murdered by the IRA in 1984, said Ms McKee was a "kind, gentle, witty and stubborn soul".
"I have just heard, that my lovely friend Lyra was murdered tonight in Derry. I just can't believe, that this witty, clever human being has been taken... Feel sick."
Fellow journalist Peter McGuire said Ms McKee was a "gifted writer, a kind person and SO generous with her time and knowledge".
"So young - horrific & heartbreaking news from Derry tonight," he tweeted.
Seamus Dooley, Irish secretary of the National Union of Journalists, wrote: "Shocked by news that woman shot dead in Derry last night has been named locally as @NUJofficial Lyra McKee.
"We are shocked by killing of a journalist of courage, style and integrity. Sympathy to her partner, family and many friends."
Lilly Dancyger, a New York-based editor at digital publication Narratively, said Ms McKee was "dedicated to covering the lasting trauma & violence of the Troubles".
"Devastating to hear she was killed tonight by that same violence," she tweeted.
Ms Dancyger shared an article written by Ms McKee about the families of Troubles victims.
"I was Lyra's editor on this story, and it was an honour. Sharing her work now is all I can think to do," she said.
Writer Brooke Magnanti, whose blogs were made into TV hit Secret Diary Of A Call Girl, said she was "stunned" by the news.
She tweeted: "I only knew her from online and a phone conversation after we were introduced by @GlasgaeLauraLee; she struck me as a thoughtful journalist unafraid to challenge her own beliefs. Rare and precious. Deepest condolences to family and friends."
Independent publishing house Faber signed two of her books last year.
Laura Hassan, editor director of the house, commented on Ms McKee's new-coming book The Lost Boys , which will explore the disappearances of a number of children and young men during the Northern Ireland conflict.
She said: "I was hooked by McKee's singular, crisp prose and I loved the blend of investigative journalism, true crime, memoir and social history in The Lost Boys.
"McKee has that knack of engaging the head and the heart."
The Ferret, an online investigative journalism cooperative in Scotland which had published Ms McKee's work, tweeted: "We are deeply saddened to hear of Lyra McKee's death. Lyra was a brilliant journalist who wrote for The Ferret.
"In 2016 she won Scottish Refugee Council and Write to End Violence Against Women awards. Our deepest sympathies go out to Lyra's family and friends."
Lisa McKee, a writer for the hit TV programme Derry Girls, tweeted: "Sickening, shameful and heartbreaking."
Mr Hamilton offered his "deepest sympathies" to Ms McKee's family.
And he said: "But not only is it a murder of a young woman, it is an attack again on the people of this city.
"I stood here in January and we talked about the bomb and the act of violence against this city, and yet again we see another act of violence in this city which has had horrendous consequences and which will affect people for many, many years.
"I would appeal to people, particularly this Easter weekend, to stay calm, I would appeal to people who are intent on violence to draw back, I would appeal to people with influence to use your influence and make sure this is peaceful weekend. Not only this weekend but going forward in this city.
"These acts of violence are bringing nothing to this city, all they are doing is bringing misery to one family, but also particularly to this city and also to our broader province."
The New IRA, an amalgamation of dissident republican factions in Derry, has been blamed for a bombing in Bishop Street, Derry, in January.
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