BOGOTÁ, Colombia—Authorities in the African place of Cape Verde detained a Colombian businessman required in the U.S. on income-laundering costs, in a blow for Venezuela’s authoritarian govt, for whom he has turn out to be an vital offer maker.

Alex Saab Morán, traveling in a personal jet, was arrested during a refueling quit on the West African island country en route to Iran, where by U.S. officials feel the 48-yr-outdated is encouraging cut specials to trade Venezuelan gold for Iranian gasoline and other oil items, in accordance…