HOUSTON (KTRK) --Houston fire fighters worked to treat the victims of Monday's active shooter, even as they heard gunfire just around the corner.
HFD's Station 3 was first on the scene, beating police there, and they went in blindly, thinking they were responding to a shooting that had already happened.
"I'm looking at the lady here. I'm looking at the damage on the second vehicle. The guy has a hole in his arm. He had been hit by a bullet and I'm hearing gunfire at the same time. It registers to me we've got an active shooter," Captain Michael Hawthorne told Eyewitness News.
There were six of them in two vehicles--a fire engine and ambulance. The uncertainty of what was happening, paramedic Victor Franco said, was most unnerving.
"Every time we heard gunshots. Is somebody coming? How bad is it going to be," explained Franco.
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In the minutes before police arrived, the firefighters were treating victims, assessing the danger and even re-routing traffic. At one point they couldn't get to a victim because of the gunfire, which is counter-intuitive to what they're trained to do.
"You just want to rush in and just want to help," Franco added.
Nine people were injured. The gunman, Nathan DeSai, was killed by police and it was also the crew of Station 3 who was asked to assess him after he was shot.
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"Is this dude dead? Is he alive? Does he have a weapon on him? Does he have a bomb on him?" Those were all the questions they had as they got closer.
It was the first active shooter scene the two veterans had ever been on. The memory will be hard to shake.
"This one has topped them all, stuck with me a little longer," Hawthorne admitted. "I've never been rattled like this."
VIDEO: Who is Nathan DeSai?