New Delhi, Feb. 19 -- The scheme began, investigators say, with a hushed message passed along by a music promoter in the Caribbean: Instead of the usual years-long wait to apply for permission to enter the United States, a visa appointment at the U.S. Embassy in the Dominican Republic could be had in as little as two weeks. All it took was $10,000 in cash - and a trusted contact inside the U.S. Drug Enforcement Administration.

According to a criminal complaint unsealed Wednesday, that DEA contact was Meliton Cordero, a supervisor for the anti-narcotics agency assigned to the Dominican Republic for the past five years. Prosecutors say Cordero leveraged his position inside the U.S. Embassy to push visa applications forward, claiming applic...