During the largest terrorism drill in U.S. history last year, the FBI and U.S. Coast Guard got into a tussle off the shores of Connecticut, fighting over how each agency's tactical assault team would be involved in the boarding of a hijacked ferry, the Hartford Courant reported. The U.S. Department of Justice's Office of the Inspector General released a report on April 3 that detailed the disagreement between agencies during the massive TOPOFF exercise, much of which was run in and around New London. That portion of the report concluded, "In our judgment, unless such differences over roles and authorities are resolved, the response to a maritime incident could be confused and potentially disastrous." It was a year ago that dozens of agencies - federal, state and local - converged on New London to respond to a massive simulated terrorism attack. While much of the focus was on a chemical weapons explosion on the New London waterfront, the Coast Guard and FBI were also responding to a mock hijacking of a 200-foot ferry in Long Island Sound. The FBI has its Hostage Rescue Team, a group with special know-how and equipment to quickly take control of a ship. The Coast Guard, the only branch of the military with law-enforcement duties, has its new Enhanced Maritime Safety and Security Team. Both were at the exercise, though the FBI was to be the lead agency in the scenario, the report explained. The FBI's position: The Coast Guard couldn't take part in the boarding because it is "very limited" when its boarding teams face an armed enemy. Also, the Coast Guard doesn't train its people to board moving vessels. The Coast Guard's take: The FBI was guarding its counter-terrorism turf. Though the Coast Guard was hoping to test its new tactical unit, "the FBI repeatedly blocked the Coast Guard's efforts." In the end, the report said, "The Coast Guard ultimately changed the scenario to circumvent the FBI's lead federal agency role." The report does not specify how the Coast Guard altered the exercise. The Maritime Transportation Security Act of 2002 left the two agencies with some overlapping duties. The subsequent Maritime Operational Threat Response, an interim plan issued in October 2005 that was to integrate national-level responses to maritime terrorism, leaves some questions in the FBI's thinking, the report said. It added, "We are concerned about how confusion over authorities will affect the two agencies' ability to establish a clear and effective incident command structure." (Source: Hartford Courant)