Workers in Shijiazhuang, Hebei province, are racing against time to build thousands of prefabricated rooms that authorities are shipping to the provincial capital to accommodate large numbers of people who need centralized quarantine.

The city reported its first locally transmitted case on Jan 2 and has seen constantly increasing caseloads.

In order to prevent potential cross-infections, particularly in hard-hit villages, residents of 15 villages are to be transferred to centralized quarantine facilities, creating a huge demand for such structures.

In response, 3,000 prefabricated rooms are arriving in successive shipments at an open space in Guying, a village in Zhengding county. The county borders Gaocheng district, an area of high COVID-19 risk where the city's first confirmed case was detected.

Cranes, excavators and other heavy machinery have roared to life as workers level 33 hectares of land in preparation for speedy construction. More than 100 workers are at the scene.

The 18-square-meter rooms have electricity, showers and a wireless network.

The project, known as Huangzhuang Apartments, will accommodate people from areas where the infection risk is high.

The work started on Wednesday and will be completed on Friday, said Zhang Cheng, a project engineer from China Railway 14th Bureau Group, one of the construction companies.

"We are sparing no effort to speed things up, because the city has seen a quick surge in cases," he said.

The apartments are the first newly built project after the province pledged on Tuesday to prepare more facilities for centralized quarantine. The effort will include building new sites and renovating existing buildings.

By Wednesday, more than 5,400 residents of the three worst-hit villages in Gaocheng had been transferred to centralized quarantine facilities. More transfers are also underway.

After spending Thursday morning assembling components, Hua Lingchao squatted beside a semi-finished room to quickly eat his meal from a take-away box.

He arrived on Thursday morning from a residential building construction site in downtown Shijiazhuang, where building was suspended due to the outbreak.

"I am so glad I can be part of building these rooms," Hua said, with a big smile. "It makes me a direct participant in our fight against the virus."

The 34-year-old said he had been out for work for almost six months. "I hope I can go home and reunite with my family during Spring Festival," he said. Hua is from Handan, a city in Hebei. "I hope we'll quickly defeat the virus, with all our efforts."

Prefab construction also has been used in other projects across the country, including the renovation last year of Beijing's Xiaotangshan Hospital, which is designated for treating novel coronavirus patients, according to Beijing Chengdong International Modular Housing Corp, one of the makers of integrated housing parts for the new facility in Shijiazhuang.

Li Lei contributed to this story.