Photo/Illutration Face masks are sold out at a drugstore in Kumamoto on Jan. 31. (Asahi Shimbun file photo)

Operators of auction and flea market sites are warning users not to exploit a shortage of face masks due to the rapidly spreading coronavirus by gouging consumers desperate to protect themselves.

Face masks are being offered online for as much as 10 times standard retail prices. In one case, 10 packages of 30 masks that typically sell for 100 yen (90 U.S. cents) each sold for 8,999 yen.

Mercari Inc., operator of leading flea market app Mercari, and Yahoo Japan Corp., operator of Yafuoku (Yahoo! auction), said stock should be offered in an appropriate price range. They also called on users not to purchase items at exorbitant prices.

According to Mercari, transactions of face masks surged in tandem with a nationwide shortage and panic demand.

The company said it had been flooded with calls about the unreasonable prices being demanded.

On Feb. 4, Mercari posted an announcement on its site asking users for their cooperation. While it has not prohibited sales of face masks, the company warned it could track how they were obtained. It also threatened to delete offers and restrict usage if people continue to abuse the service.

On Feb. 5, Yahoo Japan posted the following comment on its site: “Please give consideration so that that people who need masks are able to purchase them in the quantities they need.”

The Consumer Affairs Agency has been urging online business operators to issue warnings against users since the beginning of this month.

The National Consumer Affairs Center of Japan said it had received claims about the high prices being demanded.

Akiko Ito, who heads the Consumer Affairs Agency, said at a regular news conference Feb. 5: “People shouldn't be buying face masks to resell them for big profit because those who really need them cannot buy them. I hope people will act in a responsible manner.”