Twelve migrants have tested positive for coronavirus at a government-run shelter in the Mexican border city of Ciudad Juarez, the labour ministry said on Friday.

The gritty industrial city neighbouring El Paso, Texas, has received thousands of migrants under a Trump administration policy that sends US asylum seekers to Mexico to await the outcomes of their cases.

The migrants who have tested positive in the Leona Vicario center, which houses 337 people, have been isolated to prevent further spread of the virus, the ministry said in a statement.

‘People with COVID-19 symptoms receive medical treatment in a timely manner and remain in an isolation area to monitor their progress,’ it added, referring to the respiratory disease caused by the virus.

The migrants who have been diagnosed with coronavirus are from Brazil, Guatemala, Honduras and Nicaragua, the director of the center, Ivan Jimenez, said in an interview.

Fourteen migrants considered to be high-risk, including pregnant women and people with chronic medical conditions, were transferred to another facility, the government said.

Migrants in the shelter, one of Mexico's largest along the border, have been in isolation for more than two months, Jimenez said. Many had found work in Ciudad Juarez to support their families, but have been forced to give it up amid the pandemic.

The center has continued to supply children with educational materials during the quarantine and hopes to resume more activities as cases among the migrants dwindle, Jimenez said.

‘It's really horrible for people,’ he said. ‘Above all, our concern is for mental health.’