Both nations have tried without success since 1996 to form a cadre of trustworthy undercover Mexican investigators.

Now Mexican investigators say that his fortune is even heftier.

The Mexican investigator would not know that someone was listening in to the talk.

Mexican investigators said the crews of the two boats had been detained and charged with immigrant smuggling.

Mexican investigators have already learned that Mr. Salinas was allowed to open his private banking account without providing any bank references.

Mexican investigators say Citibank did not ask its office in Mexico City for help with assessing the new client.

Mexican investigators say they have information on more than two dozen other accounts in American banks.

Mexican investigators are now examining the payment to Mr. Salinas.

Mexican investigators say they then put out an international alert for Mr. Salinas's alias, without identifying it as such.

These deals, which are being scrutinized by Mexican, American and Swiss investigators, had little or no legal documentation.