The club from Rio de Janeiro tested 350 members of staff, including players and coaches, Vasco's medical director Marcos Teixeira said in a video on the team's YouTube channel on Sunday.

"We found 16 athletes with positive test results. They were separated from the group, they remain in medical contact and they will be tested until we are sure that they cannot transmit the virus to the rest of the squad," said Teixeira.

He said that around 30 percent of those tested "were previously in contact with the novel coronavirus," including three players.

Brazil has recorded more than half a million cases and over 29,000 deaths from COVID-19. It is second only to the United States in terms of confirmed cases and fourth globally when it comes to deaths.

Vasco are one of several teams to have restarted training after two months of lockdown, despite little sign that Brazil is over the worst of its coronavirus outbreak.

Vasco's president Alexandre Campello and Flamengo counterpart Rodolfo Landim met with Brazil President Jair Bolsonaro two weeks ago to discuss the resumption of football.

Bolsonaro has courted controversy by repeatedly railing against lockdown measures taken by state governors and has even joined protests against confinement measures.