The authorities are cracking down on profiteers, following complaints that some businesses and individuals have been reselling face masks for grossly inflated prices amid a surge in demand.

The Government's Price Controller yesterday asked a retailer at 313@Somerset mall to explain the basis for the selling prices of its masks, giving it until Monday to respond.

The Ministry of Trade and Industry said Deen Express must provide information such as the cost price of the masks and its profit margins or face a fine, though it did not state how much the shop had been selling masks for. Deen Express could not be reached for comment.

Letters of demand have also been sent to e-commerce platforms Lazada, Carousell and Qoo10 to request information on any potential profiteers on their platforms.

"Profiteering is highly irresponsible and damaging in these uncertain times," said the ministry.

Surgical and N95 masks have become highly sought after in recent weeks as the deadly Wuhan virus has continued to spread.

Minister for Trade and Industry Chan Chun Sing urged consumers not to support or give in to profiteers, and said there are enough supplies for Singaporeans.

E-commerce platforms said they will cooperate with the authorities and remove listings if necessary.

The online marketplaces said that while they do not regulate prices, they will ensure sellers do not hike prices of products used as preventative measures against the Wuhan virus to unreasonable levels.

Qoo10, which removed a listing on Wednesday for 30 "anti-coronavirus" masks advertised at $10,000, said yesterday that it may suspend the accounts of merchants engaging in any behaviour suspected to be unethical.

Carousell said sellers with unreasonable prices will be asked to review them or face having their listings taken down.

Lazada said it has internal measures in place to ensure sellers maintain reasonable prices for essential items like masks and hand sanitisers.