referring to Monday's flight carrying 73 Guatemalans from Alexandria in the US state of Louisiana to Guatemala City.

The US said on Thursday it had sent a CDC mission to assess the situation and test the migrants, who remain in quarantine in a hospital.

The Trump administration has pressured Guatemala to keep receiving migrants it deports, despite growing concern in the poor Central American nation that returnees are bringing the virus with them and could infect remote communities.

The Associated Press news agency later cited a Guatemalan official saying 44 people on Monday's flight were infected, the discovery prompting Guatemala to suspend all deportation flights from the US.

Giammattei said: "Until the agreement between the two countries is fulfilled, giving us the certainty that those people will come with a certificate demonstratingthey are free of the coronavirus, the flights of deportees are suspended."

The president said on April 4, following another flight that arrived on March 26, the US government was asked to sign an agreement to set up a protocol for bringing deported citizens and ensuring they were free of the coronavirus.

It is not clear when the deportees became infected. There have been 30 confirmed cases of COVID-19 among US Immigration and Customs Enforcement (ICE) employees working in the agency's detention facilities, including 13 at the Alexandria Staging Facility in Louisiana, ICE data shows.

Flights deporting Guatemalans from the US were temporarily suspended on Thursday after reports of the mass infection. Deportation flights had only started again on Monday after a five-day suspension because of earlier infections.

Neither ICE, which operates