It was a tense night at the Port of Charleston on Wednesday after a "dirty bomb" threat was reported in a container aboard a vessel moored there.
The U.S. Coast Guard said that authorities were notified at approximately 8 p.m. Wednesday of a potential threat in a container aboard the Maersk Memphis, which was was moored at Charleston's Wando terminal.
Coast Guard Lt. JB Zorn told CNN the threat was based on an anonymous claim shared by a man on YouTube.
The terminal was evacuated, and a unified command was established to oversee the response. Federal, state and local law enforcement agencies identified four containers aboard the Maersk Memphis where the threat was posed. The containers were scanned and cleared.
The safety zone around the terminal was lifted at approximately 3:30 a.m. when the authorities determined that there was no existing threat to the port.
Responding agencies included the Coast Guard, Federal Bureau of Investigation, South Carolina Department of Natural Resources, Mount Pleasant Police Department, Mount Pleasant Fire Department, Charleston County, South Carolina Ports Authority, National Guard Civil Support Team Unit 43, South Carolina Law Enforcement Division and the Coast Guard Investigative Service.
The original reporting source of the threat in port of Charleston has been detained by authorities for further questioning. The Coast Guard said the individual was detained in Zanesville, Ohio, on charges not related to the port incident and would be questioned Thursday by the FBI.
Zorn told a local ABC affiliate that investigators had no credible information to suggest there was a "dirty bomb" aboard the vessel and that the threat was investigated out of an abundance of caution.