Only moments after learning an explosion in the Savannah harbor had sunk a boat, law enforcement divers submerged and began their search.
The teams were tasked with locating additional explosives, scrap materials from the blast, a gun and the suspect's body.
Within minutes the first team located a backpack in the water. They brought it to land and destroyed it.
The gun was recovered next.
After searching for nearly five minutes, the final team surfaced, towing the 150-pound body toward the shore.
Though this Thursday morning disaster was only practice, its goal was to prepare law enforcement for a very real threat.
The Federal Bureau of Investigation this week is conducting its Underwater Post Blast Investigations Course in Savannah.
It's the first time the week-long counter-terrorism diving training has been hosted outside of Los Angeles, said Greg Rabinovitz, an FBI special agent bomb technician based in the California city.
The training is especially useful in cities with major ports like Los Angeles and Savannah, said Rabinovitz, who teaches the program.
Those ports could be susceptible to a situation like the scenario posed Thursday - a terrorist aboard an incoming boat armed with a firearm and an explosive-laden backpack.
"We find as much as anything that it's not the threat from a major terrorism incident - we've trained well and prepared for that - but from a small, everyday-kind of incident," Rabinovitz said. "Our goal is to be able to get through the everyday stuff quickly."
After attending the course in Los Angeles about five years ago, Sgt. Robert Von Loewenfeldt, of Savannah-Chatham police's bomb squad, hoped to bring the training to Savannah.
Because the FBI had been looking for an East Coast training center, metro police and the federal agency teamed up to bring it here.
"This is huge," Von Loewenfeldt said. "For three years I've been working to get Savannah as the East Coast training center for the FBI.
"I'm more excited than I can say."
This week, 24 public safety divers and bomb squad technicians from across the East Coast were trained in the program that prepares them to respond to underwater explosions, collect the pieces of the device and put it back together.
That allows authorities to use the blast as evidence.
"After this training, these guys can testify in court that this is what happened," Von Loewenfeldt said. "It's invaluable for this job."
The scenario was carried out at a pond - portraying the harbor - in a local training area, with real explosives, though the suspect's body was only a mannequin.
After pulling the backpack-bomb from the water, officials destroyed it with their own explosives.
"Using explosives to get rid of explosives is the safest way to get rid of them - what we call rendering them safe," Von Loewenfeldt said.
Eventually, Rabinovitz said, the Savannah-Chatham police along with Kevin Harrison, an FBI special agent bomb technician based in Atlanta, will teach the course.
Von Loewenfeldt is hopeful the course will be ready by late summer, though he admitted that may be too optimistic of a goal.
"It requires a lot of legwork," Rabinovitz said. "There is a lot of equipment and coordinating that is involved to hold this training."
Eventually though, it will be held twice a year in Savannah.
"The Savannah-Chatham (police) stepped up," Rabinovitz said. "We're hoping that the FBI-Atlanta and Savannah-Chatham can run this course by themselves very soon."