Malaysia reported 277 coronavirus cases Thursday, its biggest daily increase, due to a growing outbreak at a migrant detention centre, sparking accusations the government is failing to protect foreign workers.
The Southeast Asian nation has had a relatively small outbreak, reporting 8,247 cases in total, and imposed a weeks-long lockdown that largely kept the situation under control.
But cases have been increasing rapidly since last week at centres where foreigners are detained on suspicion of being in the country illegally.
Relatively affluent Malaysia attracts migrants from poorer Asian countries, including Myanmar, Bangladesh and Indonesia, who work in sectors ranging from agriculture to manufacturing.
Of Thursday's cases, 270 were among foreigners held at one detention centre in the capital Kuala Lumpur, senior health ministry official Noor Hisham Abdullah said.
That centre has now reported more than 600 cases, while over 100 infections have been recorded at several other migrant detention facilities.
No new deaths were recorded, leaving the tally at 115.
Rights groups have been warning for months of the potential for outbreaks at the centres, which they say are cramped, dirty and lack adequate medical facilities.
The sites "are confined quarters and the constant cycle of people entering and leaving a centre creates a perfect hotbed for spreading the virus to and from communities," said Glorene Das, executive director of migrant rights group Tenaganita.
The outbreaks have also fuelled controversy over raids in recent weeks that saw large numbers of undocumented migrants rounded up from suspected virus hotbeds and sent to the centres.
Malaysia eased its lockdown last month, allowing most businesses to reopen, but some restrictions remain.
Neighbouring Singapore has also seen major outbreaks among foreign workers living in crowded dormitories.