Facebook, which also owns Instagram, has denied they were hacked and blamed the outage on ‘a change that affected our configuration systems’.
There were claims online that the super-snowstorm that is over America’s east coast may have knocked out its servers.
While it was down Facebook said they were ‘aware’ of trouble accessing the site and added: ‘We’re working to get things back to normal as quickly as possible.’
A spokesman later added: ‘Earlier today many people had trouble accessing Facebook and Instagram. This was not the result of a third party attack but instead occurred after we introduced a change that affected our configuration systems.
‘We moved quickly to fix the problem, and both services are back to 100 per cent for everyone.’
An Instagram spokesman posted on Twitter: ‘We’re aware of an outage affecting Instagram and are working on a fix. Thank you for your patience.’
There is no word at this time what is causing the outage, and whether or not it might have anything to do with the ongoing blizzard, which is expected to dump 36 inches of snow in parts of New York, Massachusetts, Rhode Island, New Jersey and Connecticut, where key servers are based.
The headquarters of Facebook are located in Menlo Park, California – an area which has not been affected by the storm.
The hashtag #facebookdown and #socialmeltdown2015 immediately started tending on Twitter, which remains operational.
Facebook had 1.25 billion monthly active users at the end of September last year, while photo-sharing service Instagram has 300 million active monthly users uploading around 70 million photos per day.
Andrew Pope, an engineer at Facebook, posted on to the Facebook Developer’s website to alert app creators to the ‘major outage’ which he said lasted up to an hour between around 6.10am and 7.10am.
‘Our engineers identified the cause of the outage and recovered the site quickly,’ he wrote.
‘Thank you for your patience. We are sorry for any inconvenience this may have caused you and the users of your apps.’
The Lizard Squad is a group of hackers that has caused havoc in the online world before, taking credit for attacks that took down the Sony PlayStation Network and Microsoft’s Xbox Live network last month.
This morning the group tweeted ‘Facebook, Instagram, Tinder, AIM, Hipchat £offline £LizardSquad’.
Previously it claimed responsibility for the Christmas Day attack on Xbox and PlayStation games consoles which saw online services disabled.
In an interview with BBC Radio 5 Live, one of the group’s hackers, who called himself ‘member one’, said he enjoyed identifying weaknesses in the web security of global companies.
‘I wouldn’t call myself a top-grade hacker – I know people who are way better than me. It’s fair to say I know my stuff though,’ he said.
‘With me, when people, friends of mine, go out clubbing, partying, I didn’t enjoy it so I decided to sit at home and learn more skills of my own.
‘Maybe this isn’t something most people enjoy and think it was a good decision but for us it was something that we just decided upon.’
He added that ‘huge, global companies’ with teams of technicians should be able to protect their network security from hackers who have ‘barely lived’.
The latest outage sparked panic online, but the majority retained a sense of humour
Another user Gino Quillamor wrote: ‘Now that facebook is down, I might actually have to ask people how they’re feeling in real life. ‘What’s on your mind?”
Rob Lee joked: ‘If Facebook & Instagram are down how am I supposed to know what my aunt had for dinner or if any of my friends held a Starbucks cup today???’
On a more serious note, less than 30 minutes into the shutdown, a hacker group known as the Lizard Squad claimed responsibility for the outage.
In August, it also tweeted to American Airlines that there might be explosives on a plane carrying the president of Sony Online Entertainment, which makes video games, forcing the flight to be diverted.
Yesterday, it claimed to have targeted The Malaysia Airlines website, leaving a message saying ‘404 Plane Not Found’ and declaring it part of their ‘cyber caliphate’
Users logging on to the site of Malaysia’s national carrier were greeted with the picture of a lizard in a top hat, monocle and tuxedo, smoking a pipe.
The image was surrounded by the message ‘404 Plane Not Found’, an apparent reference to the airlines’ unexplained loss of flight MH370 last year with 239 people aboard.
The extent of any links with the Islamic State, however, are not yet known.
The jihadist group has seized large swathes of Syria and Iraq in a brutal campaign and declared an independent Islamic ‘caliphate’.
It also has used social media to recruit and spread its message.
