AMSTERDAM (AP) — Dutch prosecutors have raided a string of locations and seized cash and hundreds of thousands of fraudulent letters in an investigation into worldwide mail scams that U.S. law enforcement authorities say defrauded "elderly and vulnerable" Americans out of millions of dollars.

Dutch authorities said Thursday they had made no arrests but that investigations were ongoing. The American Justice Department announced that a civil complaint has been filed in the U.S. District Court for the Eastern District of New York against a Dutchman, Erik Dekker, and two companies he runs, that were among the locations raided by the Dutch on Wednesday.

According to details of the American complaint, Dekker's companies received and processed payments from the fraud schemes.

Dekker could not immediately be reached for comment Thursday.