Leona O'Neill, a local journalist at the scene of the shooting, said that after McKee was hit and fell beside a police Land Rover, officers rushed her to Altnagelvin Hospital, where she died. In a statement, Deputy Chief Constable Stephen Martin of the Northern Ireland police said they launched a probe into the killing.
She said: "A young, vibrant life has been destroyed in a senseless act of violence".
Police chief Hamilton said "a single gunman fired shots in a residential area of the city and as a result wounded Ms McKee".
"For me [it] is a very worrying situation", added Detective Superintendent Jason Murphy, the officer leading the investigation.
He offered sympathy to "her partner, her family and many friends". It was condemned by all the major political parties as well as the prime ministers of Britain and Ireland.
Seamus Dooley, Irish secretary of the National Union of Journalists (NUJ) said he was "shocked" by the killing as he paid his own tribute to Ms McKee.
Belfast-born McKee, 29, had earlier posted an image from the riots, accompanied by the words "Derry tonight".
"Our hopes and dreams, and all of her fantastic potential, was snuffed out by a single barbaric act".
McKee was an LGBTQ activist and in a vigil Friday, Canning called on others to fill the void she left.
Easter is a key date for Republicans, who mark the Easter Rising of 1916, one of the most important dates in the struggle for Irish independence.
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Mercedes boss Toto Wolff told Sky F1: "It took us by surprise, even pace on the Friday we didn't think it was possible to control it in that way".
Hamilton said the force's assessment "is that the New IRA are most likely to be the ones behind this".
Dissident Republicans are believed to be behind Thursday's shooting death of a journalist in Northern Ireland, and police have appealed for calm.
The group is also blamed for a Londonderry auto bombing that did not cause any injuries in January.
Dissident splinter groups have sought to continue.
Details of death: Died at the age of 29, when shots rang out during a riot in Derry between dissident republicans and the police.
They said more than one person was involved in the murder.
"I think yesterday we realised the vast majority of communities across the whole of Northern Ireland support police and support policing and they support the peace process".
There has been an increase in tensions in Northern Ireland in recent months with sporadic violence, much of it focused in Londonderry, also known as Derry. She grew up in a Catholic neighborhood of Belfast, the Times reports, and wrote movingly about her experiences as a gay woman and a member of Northern Ireland's post-cease-fire generation. "She was bright, she was warm, she was witty".