"Yes, there is an issue and we are working to fix," Times spokeswoman Eileen Murphy told paidcontent.org. "Our initial assessment is that this is most likely the result of a malicious external attack."
NYTimes.com became unavailable to some users beginning around 3 p.m. ET and was still not accessible for many users 2 hours later.
Security threat researcher Matt Johansen tweeted he suspected the attack was the work of the Syrian Electronic Army, a group of hackers aligned with Syrian President Bashar Assad.
Several Twitter users posted screenshots of a "Hacked by SEA" message they said they received when they went to the New York Times homepage, CNN reported.
U.S. news media have been frequent targets of the Syrian Electronic Army, which has hacked into the Twitter feeds of the Associated Press and The Washington Post, and for a brief time Aug. 15 hacked the websites of several major news organizations including CNN, redirecting them to a SEA page.
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