Washington (CNN) -- From the start, some passengers knew something was amiss. The flight attendant had asked them if the plane was in Houston.
It was in Dallas.
Then came dueling announcements from two flight attendants, the first saying the plane had mechanical problems; the second assuring passengers everything was OK.
Then, alarmingly, the increasingly excited flight attendant repeatedly declared over the public address system that she was no longer responsible for the safety of the plane, and that it was going to crash.
The whole time, the plane continued rolling toward the runway.
The Friday morning incident ended only after fellow crew members scuffled with their colleague, and when passengers helped restrain her, according to passengers interviewed by CNN.
Authorities said the flight was delayed, and that two flight attendants -- including the agitated attendant -- were taken to a Dallas hospital for treatment.
Local and federal officials said they do not anticipate criminal charges, adding to speculation that she may have suffered a mental breakdown. One passenger said the flight attendant described herself as bi-polar, and said she had not taken her medication.
The unusual incident put public focus on the nation's flight attendants, who more often are viewed as the people tasked with mediating disputes or dealing with others' aberrant behavior.
But on Friday morning, the flight attendant in the forward cabin of American Airlines Flight 2332 -- a Dallas to Chicago flight -- became the focus of attention.
"She was acting weird from the very beginning," said Whitney Bessler, a Dallas resident seated in the second row. "When we first got on the plane she was asking the passenger next to me if we were in Houston and where we were going. We kind of thought she was just making a joke."
But "before we were even taxiing she was talking about how we needed to do more cross-checks, or we needed more testing, or go back for more security, something like that," Bessler said.
Bessler and other passengers said the flight attendant got on the public address system, and appeared to be calling the pilots.
At first, "everybody was laughing because it sounded like she (had) accidentally turned on" the intercom, said Laurie Grabe of Traverse City, Michigan, who witnessed the incident from her ninth-row seat.
Then other flight attendants intervened, "telling her to turn off the PA, not to talk like that," Grabe said.
The flight attendant continued her disjointed announcements, passengers said. She said, "OK, if you (pilots) don't hear me, then I give up. I'm not responsible if this plane crashes," Grabe said. She also "said something about opening the doors."
"Everybody was starting to look at each other, like 'Oh, my God, What's going on here?' "Grabe said.
Said Bessler, "Two or three times over the PA, she talks about how the planes is going to crash, how she doesn't want the plane to crash on her watch." While some of her sentences were clear, others were just "random gibberish," Bessler said.
When the flight attendant said the plane was likely to crash, "the passenger behind me ... said, 'I'm calling 9-1-1,' " said passenger Bethany Chistakos, who was sitting in the middle of the plane. "Because ... the plane wasn't stopping. We were already on the runway, we were about literally (to) take off."
Passengers said other flight attendants and an off-duty pilot scuffled with the flight attendant over control of the microphone, and several passengers jumped in to subdue the woman. It took about five people to restrain her, they said.
They "threw her into the first row of seats and held her down," Grabe said.
Grabe said the flight attendant started "screaming bloody murder," sounding "demonic."
The attendant was taken to the hospital for evaluation, officials said. A second flight attendant who may have been injured while restraining the first one also was taken to the hospital.
An airline spokesman acknowledged the incident but said passengers were not in danger.
"We continue to investigate the details and circumstances," American Airlines spokesman Ed Martelle said.
"We will ensure that the affected flight attendants receive proper care, and we commend our other crew members for their assistance in quickly getting the aircraft back to the gate so that customers could be reaccommodated," he said.
"Our customers were not in danger at any time."
FBI spokeswoman Lydia Maese said no federal charges were filed and the agency sees no need for further investigation.
After the crew was replaced, the flight departed for Chicago at 9:46 a.m. local time, about an hour behind schedule.
CNN's Dave Alsup, Carol Cratty, Tracy Sabo and Eric Fiegel contributed to this report.