Ashley Farha had never seen such destruction. The petite, intense brunette, a vice president of the downtown developer Hamilton Properties Corp., was inspecting the Lone Star Gas buildings on St. Paul Street in November 2010. The 80-year-old interconnected office buildings were slotted for a renovation that would include demolishing most of the interiors and creating residential lofts. Farha was doing a walk-through with an investor before the work began. There was broken glass everywhere. Many of the heavy-duty locks on the office doors had been blown apart, and the doors themselves had been kicked in or sliced open.

“These doors, solid wood 3 inches thick, looked like they’d been smacked with a light saber,” she says. “You just wonder what can even do something like that to a door that big.”

As she walked floor after floor, Farha saw powder burns on the floors and walls, and bullet casings scattered everywhere. There were even shooting targets left hanging on the walls: a cartoonish burglar, an old lady with a purse and a gun, an alien like something out of Men in Black. They were all full of holes. “These were good shots,” she says, “all concentrated in the chest and head.”

Farha was told that, a week or so earlier, Hamilton Properties Corp. had rented the buildings to something called the Naval Special Warfare Development Group—known as DevGru in military parlance and as SEAL Team Six to the rest of us. This was just a few months before the American public learned all about the group of elite warriors who killed Osama bin Laden. Farha had no idea at the time that the buildings might have played a role in the biggest manhunt in history.

Now, Hamilton Properties Corp. is just finishing up dozens of lofts in those buildings, and telling people that the place served as a setting to a preamble of American history certainly wouldn’t hurt sales. But I asked someone directly involved with the SEAL program about this supposed training mission, and the person said the details didn’t add up. Would the most elite team of the Navy SEALs really shoot up a building and then just leave shell casings and paper targets? Would they even be firing live rounds in an urban setting like that, so close to so many other buildings and civilians?

Any training that involves firing indoors is complicated. The Navy uses private contractors to find buildings they can shoot up. Because combatants rarely stand in the middle of a room during a raid, SEAL teams sweep into an open space and fire back at the walls. In 2008, Petty Officer 2nd Class Shapoor “Alex” Ghane, a 22-year-old Navy SEAL, was killed in a training mission in Mississippi when a bullet came through a wall and hit him in the chest, right above his body armor. After Ghane’s death, the Navy instituted strict precautions for shooting in closed spaces. Often, contractors are asked to build special “shoot houses,” with walls as thick as the barriers of a NASCAR track. In other words, something quite unlike some condos in downtown Dallas.

Then there’s this: not a small amount of ink and film has been dedicated to that raid. We know that the military built a replica in North Carolina of bin Laden’s Abbottabad compound. Yet nowhere has there been any mention of a training mission in Dallas.

The Navy Special Warfare public affairs office will not comment on whether there was an operation in Dallas in November 2010, or whether it had anything to do with the Abbottabad raid a few months later. But the Navy doesn’t say much about DevGru. In fact, according to the Navy, SEAL Team Six, the one group that would have the most leeway to work outside the constraints of official regulations about indoor shooting, doesn’t even officially exist.

When it comes to marketing materials, Hamilton Properties Corp. does have one curious document: a contract for the use of the Lone Star Gas buildings naming the Naval Special Warfare Development Group as a party. It personally names Carlos Sandoval, the NSWDG Urban Training Coordinator. The contract is dated in late October 2010, for use of the building in mid-November, just weeks after reports say the CIA identified bin Laden.

“It’s definitely SEAL Team Six,” says Larry Hamilton, who, with his son, owns the development company. “A friend of ours knew they were looking for a building in an urban setting. He knew we had this property and that it was going to be destroyed anyway, so he reached out as a liaison.” Ordinarily, they’d charge about $2,000 per day to use the building, Hamilton says, but for the Navy they did it for free.

Farha gave a tour to a representative of the Naval Special Warfare Development Group as he was scouting the location. “They kept asking if there was anything they couldn’t demolish,” she says. “I basically gave them free rein over anything that wasn’t the exterior of the building.” She says the men weren’t interested in the open, cavernous lobby. They were more focused on the maze of long hallways and offices upstairs. They wanted to know if they could use the exterior fire escapes, if they could break old windows.

A few people Hamilton knows came to watch on the night of the practice mission. He was told that a helicopter appeared out of the dark night and hovered over the buildings. Ropes dangled from its belly and a stream of commandos dressed in black dropped onto the roof. The soldiers worked their way through the building, floor by floor, lighting up rooms as door locks were blown open. Then, as quickly as they had appeared, they were gone.

A few months later, when President Obama announced to the world that bin Laden was dead, his body buried at sea, Hamilton and Farha wondered: could those have been the same guys? There’s no way to know for sure if the men in Dallas that night were training for the bin Laden raid. But Hamilton says that the friend who connected his company with the Navy told him that he texted his SEAL buddies after the news broke, and that the warriors in Dallas were the same men who went on that famous mission.

Hamilton is still renovating the buildings. The company hopes to open 230 loft apartments by next summer. There will be a display in the building’s lobby, a shrine to that night and the strange history of the space. Some of the shell casings will be there, along with the bullet-riddled targets, the dated contract with Sandoval’s name, and photos of the destruction.

“It’s still overwhelming to think about what went on here,” Farha says. “It really is like something out of a movie.”