"Today, 122 more cases of infection were registered. The cumulative toll has reached 721," the ministry's spokesman Taweesin Wisanuyothin said at a briefing.

He specified that out of the 122 new cases, 20 people got the coronavirus from earlier infected individuals and 10 others contracted it abroad. The remaining 92 people are currently under investigation to determine the infection chain, he added.

The toll's rapid growth was due to two factors, according to Wisanuyothin — the first one being increased diagnostic capacities in Thai provinces and the second one being the government's shift to a new testing procedure.

"We used to confirm the patient's status only after getting the confirmation from two separate laboratories for each sample of biological material. Now we rely upon the results from one laboratory in each case, which has increased our laboratory capacity to process more samples," Wisanuyothin said.

According to the ministry's update from Sunday, when the toll grew almost by half in 24 hours, the majority of new patients were young people with a lack of social distancing.

The number of COVID-19 cases worldwide went above 292,000 on Sunday and the death toll crossed 12,700, according to the latest situation report from the World Health Organization.