Blizzard confirms World of Warcraft's North American servers are experiencing a DDOS attack in the wake of the release of the latest expansion to the game, Warlords of Draenor.

The attack facing servers was significant enough for the company to formally acknowledge it on the official World of Warcraft forums, with community manager Bashiok writing: "We ran into a few other issues [in NA] including a distributed denial of service attack, that resulted in increased latency."

Server maintenance on all North American realms is expected to begin at 5 a.m. PT, and will last roughly four hours.

The attack is believed to have originated in China, according to WoW Insider, while European servers are also experiencing latency issues that have resulted in long queues to enter the game.