Russia operated a state-sponsored doping programme for four years across the "vast majority" of summer and winter Olympic sports, claims a new report.
It was "planned and operated" from late 2011 - including the build-up to London 2012 - and continued through the Sochi 2014 Winter Olympics until August 2015.
An investigation commissioned by the World Anti-Doping Agency (Wada) says Russia's sports ministry "directed, controlled and oversaw" manipulation of urine samples provided by its athletes.
It says Russian athletes benefited from what the report called the "Disappearing Positive Methodology", whereby positive doping samples would go missing.
International Olympic Committee (IOC) president Thomas Bach described the commission's findings as a "shocking and unprecedented attack on the integrity of sport and on the Olympic Games" and pledged to enforce the "toughest sanctions available" against those implicated.
The IOC will decide on Tuesday about any "provisional measures and sanctions" for the Rio Olympics, which start on 5 August.
The commission, led by Canadian law professor and sports lawyer Dr Richard McLaren, looked into allegations made by the former head of Russia's national anti-doping laboratory.
Grigory Rodchenkov claimed he doped dozens of athletes before the 2014 Winter Olympics, which were held in Sochi, Russia.
Rodchenkov - described by the Kremlin as a "scandalous" former official - also alleged he had been helped by the Russian secret service, the FSB.
He claimed they had worked out how to open and reseal supposedly tamper-proof bottles that were used for storing urine samples so the contents could be replaced with "clean" urine.
McLaren sent a random amount of stored samples from "protected Russian athletes" at Sochi 2014 to an anti-doping laboratory in London to see if they had scratch marks around the necks of the bottles that would indicate they had been manipulated.
McLaren said "100% of the bottles had been scratched" but added that would "not have been visible to the untrained eye".
He said he had "unwavering confidence" in all of his findings.
The damning report does not make any recommendations, but will fuel calls for a complete ban on Russia from the 2016 Summer Olympics.
Wada has recommended the IOC "decline entries, for Rio 2016, of all athletes" submitted by the Russian Olympic Committee and the Russian Paralympic Committee. Russian government officials should also be banned from this summer's Games, it said.
Wada president Sir Craig Reedie called the "scope and scale" of the findings a "real horror story".
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How has Russia reacted?
President Vladimir Putin made the Sochi Games a showcase event and spent more than $50bn (£37.7bn) staging them.
On Monday, Putin said officials named in the McLaren report would be suspended, pending a thorough investigation.
But a statement released by the Kremlin criticised the report as "accusations against Russian athletes" based on the the testimony of "a person with a scandalous reputation".
It also warned of a "dangerous recurrence of interference of politics in sport".
Putin has asked Wada to provide "more complete, objective, evidence-based information" to Russian investigators.
BBC sports editor Dan Roan:
"How could all this have gone on under the noses of the IOC and Wada for years, in a Wada-accredited lab? Why did it take a whistleblower to unearth the corruption? And will this scandal split the Olympic movement beyond repair?"
BBC Radio 5 live sports news correspondent Richard Conway:
"It's a lot worse than people were expecting. I've read through some of the report and 580 positive tests were covered up across 30 different sports. We are into the world of James Bond-style espionage."
- Russia decided to cheat following the "very abysmal" medal count of 15 at the Vancouver 2010 Winter Olympics
- It began making positive drug tests disappear from its anti-doping laboratories in late 2011
- Before the Winter Olympics in Sochi, Russia created a storage bank of clean, frozen urine
- Russia's security service, the FSB, worked in a building next to the Sochi laboratory, swapping positive urine samples for clean negative ones through a "mouse hole", adding table salt to make them weigh the same
- A key FSB agent had access to the Sochi anti-doping laboratory, disguised as a sewage and plumbing contractor
- But, in swapping urine samples, the FSB agents left miniscule tool marks on the bottles - later found by McLaren's investigators using a microscope
- The Moscow laboratory destroyed 8,000 samples it held dated prior to 10 September 2014
United States Anti-Doping Agency chief Travis Tygart:
"The McLaren Report has concluded, beyond a reasonable doubt, a mind-blowing level of corruption within both Russian sport and government that goes right to the field of play… and most importantly, our hearts go out to athletes from all over the world who were robbed of their Olympic dreams."
British Olympic 400m silver medallist Roger Black on BBC Radio 5 live:
"It's about as bad as it could possibly be. I'm not naive, I know certain people will take drugs, but I've always said this is a minority of people. The problem now, when you're looking at a Russian athlete, is you won't be thinking that."
Britain's marathon world record holder Paula Radcliffe on BBC Radio 5 live:
"I think that a level of institutionalised doping, of institutionalised cheating and fraud to sport, which has done such damage to every sport globally has to be punished strongly. Unfortunately there will be some innocent athletes from Russia that will suffer from that ban."
British European 10,000m champion Jo Pavey on BBC Radio 5 live:
"It's just awful. You feel sorry for any clean athletes in Russia who have put their hearts and souls into qualifying for the Olympics. At the same time, so many are in this system that a strong message needs to be sent out."
Lord Coe, president of the IAAF, athletics' world governing body:
"The institutionalised and systematic doping in Russian athletics is the reason the IAAF suspended, and then upheld the suspension of, Russia Athletics Federation's membership and consequently the exclusion of their athletes from international competition."
UK Anti-Doping chief executive Nicole Sapstead:
"Now is the time for the entire sporting community to come together to find a way forward and ensure the right processes, legislation and safeguards are in place to protect the rights of all athletes to clean, fair and honest competition."
International Paralympic Committee president Sir Philip Craven:
"We are truly shocked, appalled and deeply saddened at the extent of the state-sponsored doping programme implemented in Russia ahead of Sochi 2014. The findings of the McLaren Report mark a very dark day for sport."
UK sports minister Tracey Crouch:
"Professor McLaren's report has exposed the extreme lengths some will go to in order to cheat. This shocking report is a wake-up call to the sporting world."
Bill Sweeney, British Olympic Association chief, and Ben Hawes, chair of the BOA Athletes' Commission (joint statement):
"This report realises the worst fears of clean athletes everywhere."
Gary Anderson, coach of the British bobsleigh team, told BBC Radio 4's PM:
"At Sochi, we were beaten to a medal by two Russian sleds. The revelations are greater than we anticipated so there's a lot more questions to be asked."
What about London 2012?
The report said Russia's "Disappearing Positive Methodology" worked when analysis could be done at the Moscow laboratory.
But at an international event - such as London 2012, the Athletics World Championships of 2013, or the Swimming World Championships of 2015 - Russia had to adapt its methods.
The report found:
- Dr Rodchenkov's "cocktail" of steroids was given to athletes prior to London 2012. They were drugs he felt were least likely to be detected;
- Forty-six Russian athletes with performance-enhancing drugs in their system were pre-tested from 17-22 July 2012;
- They were categorised as: red - will test positive and should be replaced; amber - traces of drugs, but should be clear for London; green - clean;
- All records of positive tests were falsified into negative results;
- Athletes were also given micro-doses of blood-booster erythropoietin (EPO) until two weeks before they left for London;
- Eleven of the 46 athletes won medals at London 2012 - some have since been banned and had their medals stripped;
- In June 2016, the IOC ordered retests of London 2012 samples and eight athletes tested positive.
How high up did this go?
It was "inconceivable" that Russia's sports minister, Vitaly Mutko, was not aware of the doping cover-up scheme, according to the report.
Mutko has been in position since 2008. He is a member of the executive committee of football's world governing body, Fifa, and chairs the organising committee of the 2018 World Cup, to be held in Russia.
The report claimed Mutko personally intervened to cover up a doping case of "at least" one overseas football player in the Russian league and that 11 positive tests by Russia footballers disappeared.
However, it was Mutko's deputy, Yuri Nagornykh, who was advised of "every positive analytical finding" from the Moscow laboratory from 2011 onwards - in "total violation" of Wada rules - and decided who to protect.
Why was the report commissioned?
The commission was set up to look into Rodchenkov's claims that he doped dozens of athletes, including at least 15 medallists, in the build-up to Sochi.
He claims this was the result of an elaborate and orchestrated plot with the Russian government, which exploited its host status to subvert the drug-testing programme. The country's government has repeatedly denied the claims.
Rodchenkov, now in hiding in the US, also alleges he doped athletes before the 2012 Olympics in London, the 2013 World Athletics Championships in Moscow and the 2015 World Swimming Championships in Kazan.
Are some Russians banned already?
Yes. The country's track and field athletes are barred from competing in Rio after the body that governs world athletics, the International Association of Athletics Federations, voted in June to maintain a global competition ban on the All-Russia Athletic Federation (Araf).
Araf hopes to overturn the suspension and will find out by Thursday if its appeal to the Court of Arbitration for Sport has been successful.
Whatever happens, a small number of Russian athletes who can prove they are clean will be allowed to compete at the Rio Games under the flag of the IOC.