Singapore recorded a single-day high of 386 new coronavirus cases yesterday, with foreign workers in dormitories accounting for a significant proportion of them.
This took Singapore's total number of cases to 2,918, as experts emphasised the scale of the task involved in the battle against the virus.
Singapore also saw its ninth death from the virus, a 65-year-old man who was confirmed to have the infection on April 9.
A week after heightened safe distancing measures kicked in, the clinical director of the National Centre for Infectious Diseases (NCID) Shawn Vasoo issued a stark warning: More lives might be put at risk if people do not take the circuit breaker measures seriously.
Dr Vasoo said that people are not taking the pandemic seriously enough, and appealed to them to be more socially responsible.
"The attitude of some members of the public is lackadaisical. More people are going to die, and unfortunately this includes more Singaporeans too if they do not adhere to the circuit breaker," he said. He called for people to stay at home, and to wear a mask when they leave for essential work and are unable to avoid close contact with others.
Dr Vasoo's warning comes amid reports that while traffic has thinned at malls, there have also been reports of Singaporeans ignoring safe distancing measures and continuing to exercise in groups, queue too closely to others and gather with those outside their household. More than 400 fines have been issued over the last two days to those found to have breached the rules.
Of yesterday's new cases, 280 were linked to previous clusters, with foreign workers in dorms accounting for the "vast majority", according to the Ministry of Health. Of the 94 cases for which contact tracing is still under way, 64 are work permit holders.
Stricter safe distancing enforcement measures that kicked in on Sunday, including fines for first offences, appear to be having some effect. The authorities said that crowds at places such as wet markets and neighbourhood centres have thinned significantly, as more heed the call to stay home.
National Development Minister Lawrence Wong told The Straits Times: "People movement around the island has reduced considerably. That is a good start. We must double down on our efforts and persevere through the rest of the month."
He added: "Stay home and keep our contact with others to a minimum. The health of all Singaporeans depends on each one of us."
Minister for the Environment and Water Resources Masagos Zulkifli said in a Facebook post last night that the remaining three weeks of Singapore's circuit breaker form "a critical window that will determine if we can successfully flatten the curve, prevent large-scale community spread, and save our loved ones".
Governments from Berlin to Washington are, meanwhile, gingerly plotting to loosen weeks of lockdowns and put their economies back on track, but fears of a second wave of infections linger.
In Europe, where strict measures have helped to bring down transmission of the virus, Italy last week extended its curbs, which had been due to end yesterday, until May 3, though it will allow a few types of shops to re-open this week. US President Donald Trump is also contemplating whether to end - against the advice of health experts - or extend national social distancing guidelines which expire on April 30.
But China, which has been slowly relaxing its movement controls after finding success in arresting the outbreak, was forced to impose stricter quarantine measures at its Heilongjiang border with Russia when some returning Chinese nationals entering the province tested positive. They accounted for nearly half of China's 108 new cases as of Sunday, its highest in nearly six weeks.