Viktor Shamayev, press secretary for Vladivostok customs said that soon after the plane from Seoul landed, passengers went through customs and proceeded to fill out their landing documents. At this point, an alarm signal went off, alerting security to a rise in the radiation level in the customs hall.

Customs officials trolled the crows with Geiger counters and found the source of radiation – a woman who had been undergoing treatment with a radio-pharmaceutical in South Korea.

The woman was briefly detained, and released after the Russian Federal Consumer Rights and Health Control Service had been notified, Gazeta.ru reported.