Story highlights First online game co-developed by the People's Liberation Army allows players to fight Japan

In one level, players are asked to defend disputed Diaoyu islands, known as Senkaku in Japan

Game developer Gu Kai says the game targets nationalistic youths in hopes of recruiting them

In "Glorious Mission Online," China's first online game co-developed by the People's Liberation Army and released to the public, players join the ranks of the country's military to take on the enemy.

The game was originally developed by China's military as a training and recruitment tool and featured Chinese forces taking on American soldiers.

But the game drew massive nationwide attention because of one level, which pits Chinese soldiers against a different enemy -- Japan.

This level is set on an island chain disputed between China and Japan. The game asks players to defend the Diaoyu Islands in the East China Sea, known as the Senkaku Islands in Japan.

Both countries claim sovereignty over the remote, rocky islands, which are near important shipping lanes, rich fishing grounds and possible mineral deposits.

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Japan currently administers the area, but since late last year, China has mounted a concerted campaign to try to change the situation.

So popular was the game in stoking nationalism amid growing tension between the East Asian neighbors over the islands, developers have officially changed the name of the island mission level to "Defending the Diaoyu Islands."

"The part where we defend the Diaoyu Islands and the aircraft combat were fun! All Chinese should play," posted @Gaici2hao. @Haidaoshengmingyue posted: "We fought with the Japanese yesterday in Shanghai and the Diaoyu Islands, it's cool."

Although interest in the game has centered on the territorial issue, game developer Gu Kai says this was not the intention.

"I think the game has been misinterpreted a little bit," says Gu, whose firm Giant Interactive Group, Inc. co-developed the game with the Nanjing Military Area Command of the PLA. Gu says the company never specified the island area as the disputed territory in the first place, and the decision to label the mission was in response to growing public interest over the topic.

The idea of using military-themed game to train soldiers or serve as a recruitment tool is not new. The U.S. army has an online game called "America's Army" that allows players to go on training missions and fight each other online.

According to Gu, "Glorious Mission" targets nationalistic youths who are attracted to online games.

A press release from Giant Interactive Group claims that the game presents a full picture of the PLA's daily operations and calls upon youths to join the army, defend their country, and strengthen the "Chinese Dream."

Gu says it is hoped the game will help recruit more recent graduates who are experiencing increasing difficulty in a declining China job market, together with well-educated college graduates.

Compared to other countries, China is relatively late in terms of using games as military training and recruitment.

"For a long time, Chinese military has been distant and mysterious to the public, but the game opens a door for young people to learn about the PLA and how the military operates," Gu says.

"The game aims to provide players with an authentic experience; even the voices are from real soldiers."