Qihoo 360, one of China's leading online security software developers, was forced to withdraw Koukou Guard, a security software that triggered a war with Tencent, China's largest dot.com firm based on market value. [Full coverage: Internet giants at war]

However, the battle may not subside soon because 360 refused to withdraw allegations that Tencent QQ, China's most popular instant messaging platform, scans the hard drives of users.

Meanwhile, Internet users and lawyers also jointed the battle, which made the conflict more chaotic.

Yin Xiaoshan, a top advisor to 360, confirmed to the Global Times Sunday that the company agreed to withdraw Koukou Guard, a downloadable tool promoted as the solution to stop the illegal scanning by blocking QQ plug-ins. It was launched on October 29.

Yin said that the Ministry of Industry and Information Technology and the Ministry of Public Security weighed in Thursday and then 360 agreed to stop allowing users to download Koukou Guard.

In a letter to the public on Saturday, 360 announced the decision, but insisted on still providing "360 Privacy Protector," a free software that identifies software that tries to monitor a user's hard drive.

The program was first introduced September 27, the same time 360 initially warned that QQ users were in danger because of the invasive scanning.

QQ, similar to MSN Messenger, is the world's largest instant messaging tool operated by Tencent and it has more than 600 million active accounts.

Despite the backtracking by 360, the war of words between the two giant companies continued over the weekend.

On Saturday, Qihoo 360's chairman Zhou Hongyi denied, through his micro-blog, Tencent's previous accusation that 360 wanted to enter the instant messaging market by introducing Koukou Guard.

A day earlier, Ma Huateng, chairman of the Hong Kong-listed Tencent, also stepped out to say he received a threatening message from Zhou's mobile number on September 29.

Sunday, QQ's software was not working on computers containing 360's anti-virus software. Tencent altered its software on Wednesday and asked Internet users to choose between the two.

Ma said on his micro-blog Sunday that QQ was under threat from 360 software.

Earlier, Tencent said that they have not agreed to back off that threat despite the offer from 360 to withdraw the software.

Some users have filed a lawsuit against Tencent accusing it of violating their rights by forcing them to choose between QQ and the anti-virus software.

Zou Hailin, a researcher at the Beijing-based China Academy of Social Sciences, said the government should punish those involved.

"The two companies can take legal means to solve the dispute. They can't jeopardize the safety of the whole Internet and their users," Zou said.

Both companies claimed the Ministry of Industry and Information Technology and the Ministry of Public Security have intervened, but the authorities have not confirmed it.