A security expert has said on Monday that he has grave concerns that Google has potentially suffered a cyber-attack from either Russia or China.
Google services went down across the UK affecting Gmail, Google Drive and YouTube, with London worst affected.
Users were unable to access their email accounts, and on YouTube people are unable to acces documents and videos.
US officials have also said that Russian hackers have undertaken their largest cyber-attack against the US in more than five years.
Russian hackers gained access to the US Treasury and Commerce Departments and other departments and monitored internal email traffic which could have compromised government bodies.
The US have said that they suffered a highly sophisticated state-level attack and the FBI and the Cybersecurity and Infrastructure Security Agency are to investigate.
Over the weekend a the high level attack led to a national security council meeting at the White House.
The Russian hacking group known as Cozy Bear or APT 29 who work for the FSB, formerly known as the KGB who are Vladimir Putins spy ageny.
It is thought that Cozy Bear hackers are linked to the SVR which is Russia’s foreign intelligence unit, similar to the UK’s MI6.
Speaking to talkRadio, Security expert Will Geddes said there is limited knowledge available currently as to what has caused the Google outage.
He said that the initial attack started in the US, and questioned are we under attack from Russia or even China.
Graham said, “Whenever something like this happens, we all kind of go what is happening, are we being attacked?
“Are we under attack by some cyber hackers from Russia or China?”
The Security expert replied: “That seems to be potentially the case.
“At the moment what we know is quite limited other than there have been sporadic outrages as people have been calling in.
“It appears that the attack was initially targeted against the US.
“There are a number of US federal departments and organisations that have also been attacked.
“So this is quite concerning, this could be the 9/11 of cyber hack attacks.
“It could be possibly a state actor behind it.”
Geddes added, “I know Google spend an awful lot of money on their cybersecurity defence.
“So to be able to take down Gmail is no mean feat.”
He added: “The sky is the limit in terms of what data they could have stolen.
“It could be to download servers from Gmail accounts, credentials to log in and the contents of those emails.
“It could be sabotage to take certain divisions or federal organisations out.
“It could be to try to extract information and then hold it to ransom.
“Take your pick, it is as big as it gets.”