The number of people who can visit "popular" spots, such as certain wet markets, will be further restricted through an odd-even date system, National Development Minister Lawrence Wong announced on Tuesday, April 21.

These spots are places where people tend to gather as they are popular, but where safe distancing is hard to enforce, he added.

Movement to popular spots limited by ending NRIC numbers

This new scheme will make use of the NRIC numbers.

Depending on the last digit of a peron's NRIC or FIN, shoppers will only be permitted entry on odd or even dates.

The measure will be introduced in a bid to tighten the country's containment strategy on the Covid-19 outbreak.

Wong said such localised controls are meant to thin out the crowds in these areas, and reduce transmission risk as much as possible.

Prime Minister Lee Hsien Loong said in his speech on the same day that some "hotspots", such as certain popular wet markets, are still a problem.

This is because large groups of people continue to gather at these places, making it hard to practise safe distancing.

Similar even and odd days strategy imposed in other countries

Other countries have restricted movements using an arbitrary marker as well.

A similar measure was introduced in Bogotá, the capital of Colombia, in early April.

Only women could go out on even days to buy basic necessities such as food, while men could do so only on odd days, Bloomberg reported.

Restriction for transgender people is determined by the gender they identify with.

Besides Colombia, Peru and Panama implemented similar gender restrictions as well.

The southern Indian state of Kerala, as part of lifting its lockdown restrictions, allowed private cars to be driven on an odd-even scheme, Times of India reported.

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