Two Fijian rugby players were arrested after failing to self-isolate when returning to the country, Fiji Rugby Union said.
The players have not been named by the federation or by police but the Fiji Sun reported one was utility Semi Kunatani who plays for Harlequins.
The club are refusing to comment.
Fiji, like many other nations dealing with the coronavirus outbreak, have strict quarantine rules for people arriving in the country.
"We strongly condemn the behaviour of these two players and their disregard for lawful instructions to self-isolate themselves," chief executive of Fiji Rugby John O'Connor said.
He added: "The Fiji Rugby family wants to put on record our great disappointment at the irresponsible behaviour of these two players putting their families and other Fijians at risk.
"Such irresponsible behaviour is totally unacceptable, and we support the actions of the Police in arresting these two players and any further action taken against them."
Kunatani, 29, signed for the Gallagher Premiership side after a three-year stint at Toulouse, and was part of the Fiji sevens side which won gold at the Olympics in Rio de Janeiro.
Meanwhile Fiji Rugby has endorsed the implementation of cost-cutting measures amid "significant financial challenges" caused by the coronavirus pandemic,.
All rugby competitions in Fiji have been shut down until further notice after the first case of the new coronavirus was confirmed in the Pacific island nation on 20 March.
"All unions globally are facing significant financial challenges and responsible financial decisions have to be made to preserve the operating ability and financial integrity of Fiji Rugby long term," O'Connor said in a statement.
Fiji Rugby's gyms have been closed and elite players are under individual fitness programmes at home, while several members of the governing body's staff have taken annual leave.
O'Connor added that contracted staff, players and coaches had reduced their work to three days a week.
"Further cost-cutting measures such as leave without pay will be implemented should the situation not improve in the near future and there's no rugby kicking off," O'Connor said.
"We're in extraordinary times with this COVID-19 pandemic. We'll continue to monitor the financial impact on our operations and also continue discussions with World Rugby and our sponsors."