(CNN) -- The website for Netflix, which hosts its popular online movie streaming service, was coming back online Monday after being down for much of Sunday evening.
"The website and watch instantly are online, but some are still having issues with activating devices," the company said on its customer-service Twitter account at about 3:30 a.m. ET. "We'll have that fixed ASAP too."
As of about 8:30 a.m., some users reported still having trouble accessing the site, while others said it appeared to be working normally.
The company first acknowledged the problem on Twitter at about 12:30 a.m., writing "Hi everyone, we're working hard to bring the website and watch instantly back up. We'll post again when everything is back online."
A message to Netflix spokespeople from CNN.com was not immediately returned Monday morning.
There was no mention of the outage on the official Netflix blog.
The Washington Post was quoting Netflix spokesman Steve Swasey Monday morning saying that the outage was caused by "a technical issue that we fixed."
With recent high-profile hacking and denial-of-service attacks by groups like LulzSec, many customers were speculating that Netflix had been the victim of such an attack.