The driver of a tram that crashed in Croydon and killed seven people will not face prosecution for manslaughter.
More than 50 people were injured when the tram derailed near Sandilands tram stop in south London in November 2016.
Driver Alfred Dorris will not face action due to a lack of evidence, the Crown Prosecution Service (CPS) said.
Corporate manslaughter charges will also not be brought against Transport for London (TfL) or the operator Tram Operations Ltd.
Prosecutors said the available evidence "does not support a prosecution".
Sixty-nine passengers were on the tram when it overturned on the morning of 9 November 2016.
When it came off the tracks, before dawn and in heavy rain, the tram was travelling at almost four times the line's speed limit.
The official report into the crash concluded Mr Dorris, then aged 42, probably dozed off moments before the tram left the tracks.
The CPS agreed that driver fatigue was "by far the most likely explanation of what happened" but said "it is clear that this was an unintended and involuntary act".
"There was no compelling evidence that the driver had done anything which he ought to have known could adversely affect his concentration or make him susceptible to falling asleep," they said.
The seven people killed in the crash were Dane Chinnery, 19, Philip Logan, 52, Philip Seary, 57, Dorota Rynkiewicz, 35, and Robert Huxley, 63, all from New Addington, and Mark Smith, 35 and Donald Collett, 62, both from Croydon.
Jenny Hopkins, head of the CPS special crime and counter terrorism division, said investigators "fully recognise the impact this decision will have on families who have lost their loved ones".
On social media Tracy Angelo, daughter of Donald Collett who died in the crash, called the decision "absolutely outrageous".
In a comment on Facebook she said: "As a family we are disgusted in this decision that we have patiently waited almost 3 years for! There were so so many lives impacted that day."
Danielle Whetter, Philip Logan's granddaughter, said her family were planning to appeal the decision.
The CPS said there was no evidence for bringing corporate manslaughter charges as it found no defects in either the tram or the track which could have caused the derailment.
Det Supt Gary Richardson, of British Transport Police, said "every scrap of possible evidence has been scrutinised".
"We know that this latest update may not be the news that many, including the family members who lost loved ones, had hoped for," he added.
Finn Brennan, ASLEF's organiser on Croydon Tramlink, called Mr Dorris "one of the many victims of this terrible incident" which he said was caused "by a lack of adequate safety systems".
Jonathan Fox, TfL's director for rail and sponsored services, said the company "continue to do everything we can to ensure that such a tragedy never happens again".
"We have introduced additional safety measures on the tram network and are implementing all of the recommendations made by the Rail Accident Investigation Branch," he said
Details about an inquest into the crash are expected to be announced next week.
A civic ceremony will take place in New Addington on 9 November to mark the third anniversary of the crash.