The Call of Duty series has found huge success with annual sequels, DLC packs galore and a paid premium service, but that doesn't work in every market. Enter Call of Duty Online, a free-to-play FPS announced today and so far only confirmed for China.

Tencent, the colossal Chinese communications company which recently picked up a stake in Epic Games, has an exclusive multi-year license to run CoDO in mainland China. Like most free-to-play games, it'll be funded by in-game item sales. Players will be able to buy customisations for weapons, gear and perks said to be "built specifically for the Chinese market."

Call of Duty Online will boast multiple modes and maps, as well as "an original story told through a series of Special Operations missions based on the Call of Duty: Modern Warfare universe." It's been in development for two years, Activision revealed today, having casually mentioned back in February 2011 it was making a F2P Call of Duty.

There's no word on whether it'll ever come westward, but we can reasonably expect Call of Duty Online to spread to South Korea and other countries where F2P reigns supreme.

"We are very excited about our relationship with Tencent and the opportunities for gaming in China," Activision Blizzard CEO Bobby Kotick said in a release. "We think China is one of the most exciting places in the world for us to grow our business and to develop innovative new games."