Police in Miami say a package that repeatedly tested positive for plastic explosives, actually contained sprinkler parts.
The Coast Guard says the package was about to be loaded on to a cruise ship when the test sparked an alert. Officials say a half-dozen tests were run, with each coming back positive.
The incident comes a day after another scare at the Port of Miami, involving three Middle Eastern men in a cargo truck. That turned out to be unfounded, and was blamed on miscommunication.