The COVID-19 Omicron variant was detected in the Netherlands before two flights arrived from South Africa carrying the virus, Dutch health officials said on Tuesday.

"We have found the Omicron coronavirus variant in two test samples that were taken on November 19 and November 23," the National Institute for Public Health said. "It is not clear yet whether these people have visited Southern Africa."

The first cases in the Netherlands had been thought to be the 14 Omicron infections on two KLM flights from South Africa that arrived in Amsterdam on Friday, November 26. 

The two infections Dutch authorities revealed on Tuesday also came before South Africa first reported the new strain on November 24 to the World Health Organization, which has designated Omicron a variant of concern.

(With input from Reuters and AFP)