UPDATE, 8:15 PM Pacific: Facebook appears to be up and running again for most users after an eight-hour outage. However, its Instagram and Whatsapp services are still having problems.

Service was restored for most users by early evening, with only scattered outages still reported on Twitter, the social media service most of the affected turned to in their hour of need.

Facebook, Messenger and Instagram were out primarily in major urban areas across the United States and Europe, along with parts of South America.

UPDATED with Facebook statement: Facebook has tweeted that, while the company continues to work on the issue, it confirms the outage was “not related to a DDoS attack,” or distributed denial of service attack.

Instagram and Facebook are experiencing at least partial outages around the world. “We’re aware that some people are currently having trouble accessing the Facebook family of apps,” Facebook tweeted Wednesday, pledging “We’re working to resolve the issue as soon a possible.”

Some users apparently were able to access the platforms but could not send or receive messages or post new content.

Facebook is keeping users update via its social media pages, saying “the issue is not related to a DDoS attack.”

DownDetector, a website that tracks outages, indicates that Facebook is down mainly in parts of New England, Texas, Seattle, California, Washington, Latin America, the UK, India, and the Philippines. Commenters on the DownDetector site report outages in Florida and Minnesota as well.

Reports of problems with Facebook’s WhatsApp also have been reported.

The story is developing…