WASHINGTON (AP) — The call came in, and within minutes, U.S. Park Police Sgt. Ken Burchell scrambled to pilot his helicopter to "what might be described as a hot zone" — the scene of a mass shooting at the Washington Navy Yard.

Burchell said he was too focused on his rescue mission to worry that he and his crew might also be targets for the shooter.

"Frankly at that point you're too busy to give too much thought to the bigger picture," Burchell told reporters a day after Monday's incident. "You've got tasks to take care of."

His chopper hovered just above the rooftop of the building where the shootings unfolded, close to the chaos below where law enforcement was swarming the base in a frantic search for the gunman.

Initially the chopper crew was searching for any sign of the shooter. A radio call came that a woman who'd been shot in the shoulder needed to be evacuated immediately from the roof.

"She needed a surgeon, she needed a hospital right away," said Burchell, who has been with the Park Police for 28 years.

It was the kind of life-or-death rescue operation that the veteran pilot and his crew perform as part of their routine duties with one exception. This time, there was a shooter on the ground who could make them an easy target.

Every second counted.

As Burchell guided the helicopter, Sgt. Dave Tolson operated the rescue basket. He saw people on the rooftop attending to the woman's wound, trying to stop the bleeding.

Another crewmember on the helicopter, armed with a rifle, provided cover as the woman was hoisted to safety.

Tolson said he tried to calm and reassure the woman, who had lost a significant amount of blood. She was still conscious and able to speak, he said.

"I found her to be extremely brave," said Tolson, adding that the woman provided information about the shootings that he relayed to other law enforcement officials. Tolson declined to say what that information was.

The woman was hurried to an area hospital for treatment. "I think it saved her life," said Tolson.

The crew also made separate trips to rescue three other people who had fled to the rooftop.

"These people were in a bad situation," said Burchell. "That's what we do, is get people out of bad situations."

Asked by reporters if the crew had a celebratory moment when their long day was finally over, Tolson said: "I think there were a few sighs of relief once we got done."