Pharmacies have set purchase limits and started to give out registration tickets in order of arrival.
Hong Kong officials have been ordered not to wear masks except in limited circumstances, in order to save supplies for medical workers.
On Tuesday night, thousands of Hong Kong residents camped out overnight after a company announced that it would release 6,000 boxes of surgical masks for sale.
The first person in line reportedly arrived at 3 p.m. on Tuesday. The waiting crowds swelled to 10,000 and stretched for an estimated four kilometers in the morning on Wednesday.
The company ended up selling its entire stock of 11,000 boxes, which were originally planned to be released over two days.
There were reportedly several other cases when people lined up overnight for masks in Hong Kong, but those were much smaller in scale.
Fear and speculation that shipments would be cut off began to spread virally on social media.
Buyers soon raided supermarkets to snap up essential items, especially toilet paper and instant food.
Hong Kong food traders have assured residents of stable supply, but added that there would be no chance for them to restock properly if panicked buying continues.
Hong Kong's food merchants urged the government to exempt cross-border truck drivers from the 14-day mandatory quarantine, which took effect last Sunday, to ensure supplies could be shipped.
Many supermarket shelves looked empty despite these reassurances.
Source: Bloomberg
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