China's Shaolin Temple, the cradle of Chinese kung fu, is demanding an apology from an Internet user who said its monks had once been beaten in unarmed combat by a Japanese ninja, Chinese media reported.
Shaolin Temple, in the northern province of Henan, became famous in the West as the training ground for Kwai Chang "Grasshopper" Caine in the 1970s "Kung Fu" TV series.
Ninjas professional assassins trained in martial arts date back to mediaeval Japan.
"The so-called defeat is purely fabricated, and we demand the Internet user to apologise to the whole nation for the wrongs he or she did," the Beijing News said, citing a notice announced by a lawyer for the Shaolin monks.
Relations between Chinese and Japanese are sensitive at the best of times, with emotions still running high over Japan's invasion and occupation of parts of China in the first half of the 20th Century.
The Internet user, calling themselves "Five Minutes Every Day", said on an online forum last week that a Japanese ninja came to Shaolin, asked for a fight and many monks failed to beat him, the newspaper said.
"The facts that the monks could not defeat a Japanese ninja showed that they were named as kung fu masters in vain," the Internet user was quoted as saying in the post.
The Shaolin temple "strongly condemned the horrible deeds" of the user, the newspaper said.
"It is not only extremely irresponsible behaviour with respect to the Shaolin temple and its monks, but also to the whole martial art and Chinese nation," it quoted the monks as saying.