Britain became the latest country Saturday to report cases of the new potentially more contagious omicron variant of the coronavirus as world governments sought to shore up their defenses by slapping restrictions on travel from nations in southern Africa.

U.K. Health Secretary Sajid Javid confirmed that two people have tested positive with the omicron variant in the southeastern English town of Chelmsford and in the central city of Nottingham. He said the cases were linked and related to travel from southern Africa…

Despite the banning of flights, there are mounting concerns that the variant has already been widely seeded around the world. In addition to the U.K, cases have been reported in travelers in Belgium, Israel and Hong Kong. Germany also said it suspected a positive case and Dutch authorities were testing whether 61 people who arrived on two flights from South Africa with COVID-19 have the omicron variant.