Oliver Wieckhorst speaks in undated footage. He is closely monitoring the situation for NABU, a German organisation focusing on the protection of the environment. (NewsX/Bee)
Picture shows graduated engineer Harald Brugger from the Vienna-based Umweltberatung consulting agency, undated. He warned that anyone getting too close to a nest of the invasive species was at high risk of getting stung "several times." (NewsX/Bee)