Facebook, Instagram and WhatsApp appear to be down with thousands of users reporting issues.
According to Twitter users, the sites are unresponsive and people cannot get access.
Google searches for 'Facebook down' have skyrocket since 8.40pm this evening. The website DownDetector, which people use to report when a site is down, has had over 16,000 reports about Facebook in the past half hour.
Instagram has also received 10,000 reports from people having issues with the app. Tech company Meta owns both the sites.
People have jokingly suggested that Elon Musk should buy Meta - the company the behind the three brands - after he sealed a $44billion (£37.9 billion) purchase of rival site Twitter.
Thousands of users reported issues with Facebook from around 8.30pm. Instagram and WhatsApp soon followed, leaving users unable to load the sites' content.
Facebook Messenger is also unresponsive for thousands of users. Posting to Twitter, DownDetector said: "User reports indicate Facebook Messenger is having problems since 3:53 PM EDT https://downdetector.com/status/facebook-messenger/
"RT if you're also having problems #FacebookMessengerdown "
WhatsApp was also down earlier in the week. On Tuesday, thousands of users reported problems with accessing the app for several hours.
A spokesperson for Meta had said: "We know people had trouble sending messages on WhatsApp today. We have fixed the issue and apologise for any inconvenience."
It comes after Musk fired several senior executives at Twitter just moments after finalising his purchase of the site.
#Instagramdown is also trending on Twitter. It is not known yet what has caused the outage, or when the sites will be back up and running.
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