Miami jurors said they could not agree on a verdict Wednesday after nearly four days of deliberating whether Venezuelan Franklin Durán came to South Florida last year to silence a business associate about a cash-filled suitcase intended for an Argentine politician.

‘‘We cannot reach a unanimous verdict,’’ the 12-member jury said in a note read by U.S. District Judge Joan Lenard. No other explanation was given.

Lenard told the prosecution and defense that she will instruct jurors to continue deliberations on Thursday, noting the trial lasted almost two months and deliberations just four days.