SINGAPORE - There were empty seats on the city-bound MRT, and when the train pulled into Raffles Place station, there were no mad dashes. It was not the usual weekday morning in the Central Business District on the first day that Singapore went into "circuit breaker" mode on Tuesday (April 7).

With most workplaces shut, traffic was light after parents dropped off their children at school - the last day before full home-based learning kicks in on Wednesday.

In the heartland, wet markets, hawker centres and other eateries were open but it was takeaways for all.

The measures are aimed at containing the spread of Covid-19, which has infected 1,375 in Singapore as of Tuesday.

Mr Kevin K, 41, who works in a bank in Raffles Place, said that while the usual peak hour crowd had begun dispersing from a few weeks back, when some people started working from home, Tuesday's foot traffic was the lowest he had ever seen on a working day.

"You can close your eyes and walk around, and it would probably take quite a while before you hit anyone," he said.

Mr Kenny Chua, 38, also a bank employee, said: "I think the full impact will be felt tomorrow when the schools close."

Banks that provide essential services are among the workplaces that are allowed to remain open, though many have scaled back on the number of staff working from the office.

At Marine Terrace hawker centre, vendors told customers: "Only takeaways."

Hawker stalls had put away their bowls and utensils, with only takeout containers available.

"If customers eat here, they will be fined and so will we," said wonton noodle seller Yeung Nai Har. "We are preparing less food so that there is less wastage."

While not as packed as it was over the weekend, Ghim Moh Market was crowded on Tuesday morning with shoppers doing their marketing.

Mr Billy Yeo, who helps to run a meat stall at the market, said that business was slightly brisker than usual for a Tuesday.

"They're also buying more because there are more mouths to feed now that everyone is at home," said Mr Yeo, 28.

For those who work at the market and adjacent food centre, however, finding a place to eat has been a challenge, he said.

"Some of the hawkers have been scolded for eating in front of their own stall. But they still need to eat. Everyone should just be logical and make safe choices," added Mr Yeo.

At the Ghim Moh Food Centre, most observed safe distancing rules as they queued for their takeaways. While some stalls had long lines, others were hit hard by the drop in office crowds.

A fish soup stall had no customers all morning, said its owner, who gave his name only as Mr Gao. "Everyone is cooking at home now. If it continues like this for one month, we're done for," he said in Mandarin.

At the Bedok Interchange Hawker Centre, officers from the National Environment Agency were seen during lunchtime advising patrons to keep 1m apart in queues and to avoid eating at tables.

At a nearby coffeeshop, which had been cleared of tables, Singapore Food Agency officers also reminded stallholders of the stricter rules.

A total of 2,600 officers from various government agencies were deployed across the island on Tuesday as safe distancing ambassadors and enforcement officers.

Some people who were out to buy food or groceries said leaving the house was like stepping into a new world.

Polytechnic student Low Chiew Ming, who was at Bedok Interchange Hawker Centre to buy lunch, said: "It's very different, usually this place is very crowded."

The 19-year-old added: "It's a bit hard to stay home for one month, the new measures are inconvenient but they're necessary."

Shopping malls across the island were eerily quiet, as most shops had closed.

Orchard Road was a ghost town when The Straits Times visited on Tuesday afternoon. Walkways were deserted, with even the ubiquitous ice cream carts nowhere to be found. The usual buzz from chatter and buskers performing were replaced by the hum of light traffic on the roads.

The three malls in the heart of Jurong East - Jem, Westgate and JCube - that are usually crowded at lunchtime had little footfall on Tuesday. While most stores were shuttered, supermarkets proved to be the busiest. At Jem's Fairprice outlet, barriers were set up for crowd control but it was not needed due to the small number of shoppers in the store.

Nex shopping mall was deserted during lunch hours, save for the pockets of people waiting outside eateries for their food takeouts and those at the supermarkets. Stores were shut and lights were off for most parts of the seven-storey mall.

Serangoon MRT station - usually packed between 8.30am and 9am on weekdays - had been emptier in the morning. The station serves as an interchange for the North East and Circle lines.

There were fewer people than on a Sunday, with no queues at any of the platform doors, The Straits Times observed.

City-bound service was frequent, with trains arriving well within two minutes, and often, within one minute. Of the 12 trains observed, seats were available on all.

A customer service officer said there were schoolchildren earlier, so the platform was a little more crowded. But she expected that to thin out when full home-based learning starts on Wednesday.

Meanwhile, Transit Link said it will refund unused value of the monthly concession passes of all concession cardholders that were purchased before April 4.

The refunded amount for all concession groups will be pro-rated based on the period from Tuesday to May 4, and for students shifting to home-based learning, from Wednesday to May 4, or up to the pass expiry date, whichever is earlier.

Concession cardholders who wish to purchase a new pass can visit TransitLink's Ticket Office to use the refunded amount to offset the cost of a pass.

Otherwise, they can redeem the refunded amount as a transport e-voucher that can be used to top up their travel cards from May 5.