Chinese authorities locked down the Myanmar border city of Ruili this week to contain a surging number of new coronavirus cases throughout the southwestern province of Yunnan.

Provincial Communist Party authorities in Yunnan reported 29 new cases of the Chinese coronavirus throughout the province on March 31 “including 23 cases without symptoms. Among them, 12 patients are Myanmar citizens,” Hong Kong’s Apple Daily newspaper reported.

The majority of the new coronavirus cases were detected in Ruili, where local government officials imposed a strict lockdown on Tuesday to contain the spread of the new cluster. Government authorities completely sealed off a residential compound where most of the city’s new infections were detected and closed all businesses except for supermarkets and drugstores. All Ruili residents have been ordered to enter a week-long home quarantine.

“Each household can only send one person for groceries each day,” a local resident named Tsui told Apple Daily on April 1. The government’s restrictions on food purchases have caused many Ruili residents to panic over possible supply shortages. Tsui said she has witnessed some people “fighting for food” at a local supermarket.

“The city also ordered a crackdown on people who cross the border illegally, anyone who shelters them, and those who organize such border crossings,” the Associated Press (AP) reported on March 31. Ruili residents told the AP that Communist Party authorities recruited local government workers to monitor the Myanmar border in shifts.

“A military and police crackdown on protesters in Myanmar may be driving more people across the border, though it is difficult to gauge,” the news agency noted. Pro-democracy rallies have seized Myanmar over the past two months as citizens protest a February 1 military coup that ousted Myanmar’s elected government and threw the country into political chaos.

Chinese state media blamed a previous coronavirus outbreak in Ruili in September on people entering the city illegally from Myanmar. A China Central Television (CCTV) news anchor on Wednesday urged Communist Party authorities in Yunnan to crack down on illegal border crossings in Ruili and questioned whether officials had taken sufficient precautions since the coronavirus outbreak last fall.

“Does the loophole remain unsealed? Or have the measures been slackened? This must be thoroughly investigated,” CCTV anchor Gang Qiang said.

Deputy Governor of Yunnan Province Wang Yubo said on Tuesday that local Communist Party authorities will begin testing all Ruili residents for the Chinese coronavirus “at top speed.” Ruili has a population of 210,000 people.