BEIJING (Reuters] -China’s Xian tightened travel restrictions within Beijing on Monday, as it began a new round testing following the fifth day in a lockdown for its 13,000,000 residents.

Xian reported 150 local symptomatic coronavirus infections for Sunday. This is a small drop in the number of 155 cases from Sunday’s previous day. Officials warned people who flout rules regarding travel and testing that they could be detained and subject to fines.

Although Xian’s cases are still small compared to other clusters, officials in the city have imposed strict travel restrictions on those who leave and within it as part of a government effort to stop outbreaks.

The Omicron variant has not been confirmed in any of the 635 cases that were reported to authorities by Xian between Dec. 9 and Sunday. China has only identified a few Omicron cases among its international visitors and south.

China had 162 confirmed domestic cases of symptomatic disease for Sunday in China, compared to 158 the day prior. The highest reported count of domestic symptomatic cases since official bulletins began to distinguish symptomatic carriers at the end March.

Xian residents are not allowed to leave the area without permission of their employers or local authorities since last week.

Except for those vehicles that are used to control viruses and protect people’s lives, there will no longer be any cars allowed on the streets starting Monday. Violators could end up spending as much as 10 days in jail and 500 Yuan ($78.48).

On Monday, the city advised residents not to go home until they have given samples for a second round of testing. The city government stated that people living in areas less at risk would be permitted to purchase necessities, even if testing proves negative.

Anybody who fails to comply with the testing guidelines, which include keeping at least one metre apart in queues during testing could be subject to detention or a fine by police.

Xian launched a campaign to disinfect the entire city. Workers spray the pathogen-killing solution onto streets and buildings.

Dongyan Jin is a University of Hong Kong virologist who said that mass disinfection of outdoor surfaces and air seemed inadvisable because of the low chance of COVID-19 being caught from surfaces outside or people living so close to the surface.

Jin stated, “This means shooting mosquitoes in cannon.” He said however that disinfection was important indoor surfaces in particular places visited by people infected.

Two other cities of Shaanxi, the same province that Xian is from, and Guangxi and Zhejiang provinces were also infected.