Reuters reports that “four of Iran’s Islamic Revolutionary Guard Corps (IRGC) vessels ‘harassed’ a U.S. warship on Tuesday near the Strait of Hormuz, a U.S. defense official said, amid Washington’s concerns about Iran’s posture in the Gulf and in the Syrian civil war.”

“The official, speaking on the condition of anonymity, said on Wednesday that two of the Iranian vessels came within 300 yards of the USS Nitze in an incident that was ‘unsafe and unprofessional.'”

“The vessels harassed the destroyer by ‘conducting a high speed intercept and closing within a short distance of Nitze, despite repeated warnings,’ the official said.”