A previously unknown Dutch mole helped plan and implement the U.S.-Israeli Stuxnet cyberattack which caused serious setbacks for Iran's nuclear program beginning in 2007, according to intelligence sources. In 2004, the CIA and Mossad asked for assistance from the Dutch intelligence agency AIVD, which had already recruited an Iranian engineer. The engineer then posed as a mechanic working for a front company to infiltrate Iran's nuclear facilities at Natanz. The mole gave crucial data to the United States and Israel for the development of Stuxnet and later transmitted the virus at Natanz via a USB flash drive. Kim Zetter and Huib Modderkolk, Yahoo News, 9-2-19.