NEW YORK — Facebook users have been complaining about problems at the social media site.

Users in the U.S. and other countries reported problems lasting at least half an hour on Saturday morning. Some could not log in, and the site was unusually slow for others. Many used Twitter to complain.

Facebook, which has more than 400 million users, has generally avoided such hiccups. Twitter has had bigger problems. Last August, hackers shut down the short messaging service for several hours. Facebook also experienced problems, but it was never shut down completely.

A Facebook representative says the company is looking into the problem. (AP)