Prime Minister Prayut Chan-o-cha on Tuesday set up a panel to probe gambling dens, admitting they existed in several provinces.
The prime minister pledged to use the toughest measures against any place found to be spreading the coronavirus, including gambling dens, saying he had set up a panel to track down and punish the offenders.
The panel consists of officers from the Royal Thai Police, the Department of Special investigation, the Anti-Money Laundering Office and the Public Sector Anti-Corruption Commission.
The premier also warned the public against gambling in neighbouring countries, saying people from Thailand must not try to sneak out of the country to gamble elsewhere.
All those who have visited gambling dens were encouraged to enter the government's Covid-19 screening system, he said, reassuring them the government would not punish them.
On Monday, deputy PM Prawit Wongsuwon claimed there were no such illegal activities because the police had clamped down on them, despite warnings by a senior health official that such premises posed a serious coronavirus threat.
Bangkok Metropolitan Administration spokesman Pongsakorn Kwanmuang denied reports some of those infected people had contracted the virus at casinos in Bangkok, saying the Disease Control Department had told him they had been infected at casinos in Pattaya.
Meanwhile, national police chief Pol Gen Suwat Jangyodsuk said there was not yet sufficient evidence to take legal action against gambling dens.
However, he vowed they would be prosecuted as soon as sufficient evidence was found against them.
Pol Gen Suwat added the PM was concerned about gambling dens since many new Covid-19 cases were people who had visited such venues in Bangkok and the eastern provinces.
The national police chief said he had instructed the chiefs of the Metropolitan Police Bureau and Provincial Police Region 2, which oversees the eastern provinces, to suppress gambling.
Any officer found to be involved in illegal activities would be permanently transferred, he said.
Meanwhile, 20 gamblers -- eight women and 12 men -- have been arrested while playing baccarat at a house in the Banphot Phisai district of Nakhon Sawan. They told officers that they had fled Covid-afflicted Phichit to gamble in Nakhon Sawan. It is not known who tipped off the police.
Chief of the Nakhon Sawan provincial police Pol Maj Gen Phiraphong Sukphaibun said police had pressed charges and contacted the local public health authorities to test all 20 gamblers for Covid-19.
Police officers in the area where the gambling den was located would be investigated and punished where necessary, Pol Maj Gen Phiraphong said.
Bingo gamblers have also arrested in Amphawa, Samut Songkhram, where a high number of local transmissions has been reported.