NEW YORK - Facebook says it is aware of outages on its platforms including Facebook, Messenger and Instagram and is working to resolve the issue.

According to downdector.com, which monitors websites, the outages started around 12 p.m. EDT on Wednesday in parts of the U.S., including the East and West Coast, parts of Europe and elsewhere. Both Facebook’s desktop site and app appeared to be affected. Some users saw a message that said Facebook was down for “required maintenance.”

Facebook did not say what was causing the outages. As of 4:45 EDT service was restored to some but other users were still reporting problems.

Via its Twitter account, Facebook said the outage was not due to a “distributed denial of service” or DDoS attack, a type of attack that hackers use to interrupt service to a site.