Some Facebook users were shut out of the social networking service as the website was beset by technical troubles for the second day in a row.
"We're currently experiencing some site issues causing Facebook to be slow or unavailable for some users," Facebook said late yesterday.
"We are working to resolve this issue as quickly as possible."
The Palo Alto, California-based firm did not indicate the cause of the problem.
On Wednesday, trouble with a third-party networking provider was blamed for stopping some Facebook users from connecting with the cherished online social network that boasts more than 500 million members worldwide.