The International Olympic Committee is coming under massive cyber-attacks during the Rio Games, it has emerged.
"Throughout the Games, the same in London (in 2012) when you are the centre of attention of the world, there are massive attempts every day, all day long, to break our security," IOC spokesman Mark Adams said.
"We have it all year round anyway but it's particularly intense at the moment."
The IOC was coming under "regular attack", he said.
The Court of Arbitration for Sport warned earlier this week of attempts to break into its website. The sports court is overseeing doping sanctions at the Olympics for the first time.
The World Anti-Doping Agency (WADA) has disclosed a successful breach of its system by hackers who gained access to Russian whistleblower Yulia Stepanova's account for the ADAMS database, which tracks athletes for drug testing.
The 800-metre runner and her husband provided evidence that exposed the doping scandal in Russian athletics. Stepanova has been barred from competing in Rio because she served a past doping ban.
Wada said Saturday that Stepanova's password for ADAMS was "illegally obtained, which allowed a perpetrator to access her account".
The database is used by athletes to enter so-called "whereabouts" information which they are obliged to provide in order to make themselves available for drug testing outside competitions.
Someone with an athlete's credentials could potentially change that information, sending testers to the wrong location, potentially leading to athletes being wrongly blamed for missing a test.
Users of the database have been receiving so-called phishing emails disguised as official Wada communications requesting their login details.
"Through Wada's regular security monitoring of ADAMS, the agency noted that someone, other than Ms. Stepanova, had accessed her account," the agency said. "Wada immediately locked Ms Stepanova's account to prevent further access and notified her of the situation."
Meanwhile Olympic officials have given up on cleaning the green-tinged water in one of the pools at the Maria Lenk Aquatics Centre. Instead, they began draining it on Saturday and planned to transfer nearly one million gallons of clear water from a nearby practice pool in time for Sunday's start of the synchronised swimming.
Mario Andrada, a spokesman for Rio 2016, said the "radical measure" was necessary to ensure clear water for both judges and competitors during an event that requires swimmers to spend much of their time underwater.
He reiterated that the kale-coloured water posed no risk to the health of the athletes. An adjacent, smaller pool will continue to be used for the diving competition, even though it remains murky. American diver Abby Johnston has dubbed it "the swamp".
"Of course it is an embarrassment because we are hosting the Olympic Games," Mr Andrada said. "It should be light blue, transparent. We could have done better in fixing it quickly. We learned a painful lesson the hard way."
The water in the diving well turned a dark shade of green on Tuesday and the larger pool began to turn the same colour the following day.
Gustavo Nascimento, director of venue management for Rio 2016, blamed a contractor for mistakenly dumping hydrogen peroxide into the pool late last week, which caused an adverse reaction when it mixed with chlorine.
The dirty water will be disposed of using the city's sewage system, which has already come under intense scrutiny for dumping untreated waste into waters that are being used for rowing, canoeing, sailing, triathlon and open water swimming.
There are two warm-up pools at Maria Lenk, and neither was affected by the issues inside the stadium. The one used by water polo teams will be drained since it is not needed after Saturday, while the synchronised swimmers will continue to have use of their practice pool.
Some divers have said the green water actually helps them during competition by giving them a contrast with the blue sky when they are spinning through the air, but o thers had a different view.
"Today was pretty gross," Australia's Maddison Keeney said after Saturday's competition.
"You're standing on the stairs and you can't see your feet, one and half metres down. When you're standing up there it's a bit off-putting.
"I've never had a pool like this ever before. I just try to close my eyes and close my mouth. Hopefully I am going up and not down."
There were plenty of sarcastic posts on social media. After the diving pool was closed for a scheduled practice session on Friday, Germany's Patrick Hausding posted a couple of pictures, one holding his nose with the caption: "Good morning from the green lake!"
Mr Andrada stressed that Rio officials had been able to solve myriad issues plaguing the Games, but conceded they were out of short-term options when it came to the green water.
A day before, he attempted to explain trouble fixing the water by declaring that "chemistry is not an exact science".
"This is probably the only problem we were unable to solve quickly," he said. "The embarrassment won't last forever."