Japanese cosmetics maker Pola apologized for a poster described as racist that was hung on the door of one of its outlets on Saturday barring Chinese customers.

The apology came after Chinese social media users shared a photo of the red-lettered poster, which said, "No entry by Chinese people".

The message was handwritten in Japanese, but is understandable to Chinese readers.

It was not clear where the sign was posted.

"We are sincerely sorry and regret that an inappropriate poster ... has caused unpleasant feelings and nuisance to many people," Pola said in a statement issued on Saturday in Japanese and Chinese on its website in Japan as well as on its account on Sina Weibo.

The company said it had identified the outlet and had the sign removed. It did not specify where the shop was.

"Our company takes this issue seriously. ... We will suspend operations at the shop and punish those responsible as soon as we confirm the facts of the matter," it said.

Chinese netizens questioned the company's sincerity, despite the apology, with many saying the apology was not written in Chinese first.

Some complained there was no apology letter on its official Chinese website, but one was posted on an obscure page on its site.

"It is an apology to the Chinese people, however the company only had a Japanese apology letter on its website at the beginning." Sina Weibo user Xinxiu604 said.

"Do they really think their products are irreplaceable?" asked another Sina Weibo user, Paopaobubbling.

Attempts to reach the company's Chinese office in Shanghai were unsuccessful.

AFP and Reuters contributed to this story.