Two groups, each comprising 20 people or more, are under investigation for allegedly breaching safe distancing rules at Singapore's nature reserves.
One involves 26 hikers who attempted to go off-trail illegally in the Central Catchment Nature Reserve, the largest on the island.
The other is a group of 20 who gathered for a birthday celebration at Labrador Nature Reserve, said the Ministry of Sustainability and the Environment (MSE).
Of greater concern is that these two groups are not the only ones being investigated for possible violation of Covid-19 safety measures, nor are they the biggest groups.
The ministry revealed on Thursday that a group of 50 people is also being investigated. The New Paper understands this is the largest group linked to such a breach since safe distancing measures were put in place in March.
Responding to queries from TNP, an MSE spokesman said these incidents are among a spate of recent cases involving 12 to 50 people intermingling in large groups at various parks, birthday celebrations, baby showers, food and beverage outlets, and basketball and football games at Housing Board estate courts.
These cases are under investigation and the appropriate enforcement action will be taken, she added.
Noting the recent increase in such gatherings, the spokesman added: "It is important for all of us to remain vigilant and adhere to safe distancing measures to avoid a resurgence of cases as seen in other countries.
"We have been able to keep the number of Covid-19 cases low due to the majority playing their part.
"With the festive season coming up, and as we make the transition to phase three, it is even more crucial for us to adhere to these measures so that we can continue to keep our community safe."
Under the current phase two of the country's reopening, social gatherings of up to five people are allowed with safety measures such as the wearing of masks.
Minister for Sustainability and the Environment Grace Fu voiced concern in a Facebook post on Tuesday about the "increasing number of flagrant violations of the rules".
Infectious diseases experts warned that this is not the time for complacency, despite the drop in community cases.
With reciprocal green lanes established between Singapore and countries like Malaysia and Japan and the imminent air travel bubble with Hong Kong, an undetected case of the virus could slip through, said Dr Leong Hoe Nam, a specialist at Mount Elizabeth Novena Hospital.
"Our defence of masks and social distancing must hold. If not, we will see a new wave of community spread," he added.
"I would encourage everyone to not give up the huge gains that we have achieved."
Another expert, Dr Ling Li Min, who is also based at Mount Elizabeth Novena, said the recent rise in breaches suggests that people may be suffering from Covid-19 measure fatigue.
However, she stressed the importance of remaining socially responsible, as studies have shown that gathering in large groups in close proximity results in an estimated secondary infection rate of up to 53 per cent should someone in the group have the virus.
"Getting to where we are now with our low community infection rates has been a challenge, and we have seen from the experiences of other countries how easy it is for a new cluster of infections to form," she added.
"Let us not be tempted to let our guard down now."