EXCLUSIVE — The Department of the Treasury’s Financial Crimes Enforcement Network is increasing its efforts to crack down on a suspected sanctions loophole in Iran, in which authorities use religious charity networks to finance the government’s activities.

FinCEN sent out an alert to financial institutions demanding they report potential Iranian government abuses of these religious charitable networks, which have long been suspected of being used to circumvent sanctions. The new effort is part of Operation Economic Outcast, referred to by President Donald Trump as “Economic D-Day.”