Well the article says:
The two Gulfstream planes, reportedly equipped with the IDF's finest intelligence means, flew through Turkey, Bulgaria, and Romania before entering Hungary's airspace, the media outlets said. The aircraft were said to leave Hungary after completing their mission, without ever landing in the country.
and at some point some Syrian national was assassinated in Budapest, Hungary. The news does not make it clear how close the two events were, but the implications are clear.