DALLAS (AP) -- Amusement park employees discouraged bystanders from trying to save a woman trapped underwater after a ride malfunctioned and did not immediately try to help her themselves, witnesses said.

The accident at Six Flags Over Texas on Sunday resulted in the woman's death and injuries to 10 other people.One witness, a certified dive instructor trained in water rescue, said Tuesday that employees apparently made no immediate attempt to enter the water and told patrons to stay back.

"I heard from the staff, the uniformed park staff, 'Ma'am, do not go in the water,' " said Wendy Crown, 44, who was visiting the park with her 7-year-old son.

Six Flags spokeswoman Nancy St. Pierre said employees of the Roaring Rapids ride, in which large, round boats go through a series of rapids, are told to stay on the dock and activate an in-house emergency response system during a mishap. Help arrived within two minutes, she said.

"We had a great number of employees converge on the scene and begin the rescue efforts almost immediately," she said.

Twelve people were aboard the raftlike boat that separated from its inner-tube base as it overturned. Crown said she and others disregarded staff instructions to stay out of the 4-foot-deep water because every minute was crucial.