“It’s bad now, but we’re more worried about what’s going to happen if this persists for the next few days and the holiday weekend,” said Sam Liu, 62, who has worked at Jim’s Tailors  for six years. “I’ve never seen anything like this.”

The centre’s Harcourt Road entrance was closed on Monday.

Kwok Mo-ching, owner of City Office Supplies,   said the shop had done less than a tenth of its usual business as suppliers could not deliver stock and her staff could not go out to make deliveries.

“Normally I’d be out making deliveries all day but I’ve been sitting here all day instead. The merchandise is just piled up here in a corner,” Kwok, 51, said. “It’s put me in a very bad mood.

“Some of our regular customers called to ask if my shop was open, and I had to give them directions for how to get here. The situation is very bad for business.”

Kwok pointed out that the McDonald’s  outlet in the centre – which had a near-captive audience of hungry protesters – also had to close after running out of stock by 3.30pm.

Elen Ho said she had served just one customer at Rare and Fine Wines  all day, more than 90 per cent down on a normal day. She said the sales were on a par with those during a strong typhoon.

In Central, many shops in the upmarket Landmark mall were closed by 6.45 pm. Jimmy Choo and Dior remained open, while others such as Celine and Tod’s were closed.

Most stores are open until 7.30pm on weeknights, the mall’s website says. A notice on the window of handbag and clothing store Celine said the store would close at 6.30pm.

In Mong Kok, at least a dozen jewellery shops – including branches of Chow Sang Sang and Lukfook – were closed near an occupied section of Nathan Road.

But a luxury watch retailer based within 100 metres of the sit-in was undeterred by the protests and chose to open as usual.

“I am not scared at all. If anyone tries to bother us, we can always fight back” the manager of Valuable Watch  said.

But the manager disagreed with the pro-democracy protesters and believed their actions would “ruin” the city. “What good did they do?” she asked.

Some banks also closed their branches and service centres near the main protest zones in Admiralty, Causeway Bay and Mong Kok.

In Causeway Bay, the popular Sogo department store – yards from the famous crossing on Hennessy Road which is the focus of the sit-in – closed its doors at about 6pm on Monday, far earlier than usual.

Many other shops – from high-end retailers like Hermes to mid-range names like Body Shop – were also closed.

Retailers are anxiously watching how the protests develop. Year-on-year retail sales have shown declines for every month since February as mainland tourists spend less amid an economic slowdown and a crackdown on corruption at home. There were predictions already that this golden week would be the most disappointing in years.

Commuters also saw their journeys delayed. More than 200 bus routes had to be either diverted or cancelled on Hong Kong Island and in Kowloon. With bus services hit, MTR trains were carrying more passengers than usual even at off-peak hours.

Reporters: Alan Yu, Cheung Chi-fai, Raquel Carvalho, Alice Woodhouse