Between 27 September and 8 October 2021, various EU and national law enforcement agencies cracked down on transnational crime at the EU’s eastern and south-eastern land borders. The joint action days code-named “Finestra” were led by Frontex and the Romanian authorities. They also involved OLAF, Europol, Eurojust, the European Border Assistance Mission to Moldova and Ukraine (EUBAM MD/UA), Interpol and the World Customs Organization (WCO) as well as law enforcement authorities from 13 countries. The operations above all targeted smuggling of excise goods, human trafficking, and related document fraud. They resulted, inter alia, in the detection of 36 million illicit cigarettes, 2360 kg of tobacco, 160,000 litres of alcohol as well as 6000 litres of mineral oil; 32 smugglers were arrested. OLAF provided support through the facilitation of information exchange and checks of information against own intelligence.