Software companies have denied reports of a government ban on Web browsers that allow users to cut ahead of others when buying train tickets online.
Popular software providers Beijing Kingsoft Software and Qihoo 360 both had the controversial programs available for download on Sunday.
The browsers have add-ons designed to help people buy seats at 12306.cn, the Railways Ministry's official ticketing website, and have been popular before the Spring Festival travel rush.
However, critics say the software gives some people an unfair advantage, while media reports suggested officials were considering a ban.
Jin Lei, a marketing manager at Beijing Kingsoft Software, which makes the Liebao browser, said on Sunday that business was continuing as normal.
He confirmed that company representatives had met with ministry officials, but declined to disclose more details. "The issue is still under discussion," he said.
A spokesman for Qihoo 360, who gave her name only as Zhao, also dismissed talk of a ban. She said the company had received a notice on Friday night from the Ministry of Industry and Information Technology urging software developers to ensure the security of 12306.cn and to not do anything that may cause a system crash.
Since Jan 8, Qihoo 360's browser has helped 3 million Internet users get train tickets, Zhao said.
However, according to a female receptionist at 12306.cn headquarters on Sunday, customers are being advised not to use such browsers or plug-ins due to privacy and security concerns.
The browsers recently caused servers at Github, one of the largest code-management websites, to break down, the Mirror Evening News reported.
"The Liebao browser and the plug-ins are totally safe," said Jin at Kingsoft. "We only help customers search for ticket information, which will not affect the servers of 12306."
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