More than 40,000 users have reported Elon Musk’s social media platform X being down in the U.S., according to Downdetector.

The app and site appeared to be working as of 2:15 p.m. ET. Musk wrote on X that the company is currently “tracing” the cause.

“There was (still is) a massive cyberattack against X,” Musk wrote. “We get attacked every day, but this was done with a lot of resources.”

Reuters reports that more than 10,800 users in the U.K. also reported outages. X did not respond to a Reuters request for comment.

According to Tom’s Guide, X experienced several outages on Monday beginning in the early morning hours Eastern Time.

Major cities including New York, Boston, and Los Angeles experienced the most outages.

X, formally Twitter, is usually the place people go to find out if a social media site or website is down. But where do people go when it is X that isn’t working? Reddit, perhaps?

A screenshot of X.com not loading at 12:15 p.m. on the Safari web browser.

When Did X Stop Working?

Users began reporting issues at around 6:30 a.m. ET on Monday.

Although the site briefly began working again around 10:45 a.m. ET, both the app and website appear to still be down as of 12:15 p.m. ET.

X was working again (at least for this reporter) at 2:15 p.m. ET.

This is a breaking news story and will be updated.

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