Witnesses say passenger fell to her death from the Texas Giant ride at Six Flags amusement park in Arlington

A woman riding a rollercoaster at an amusement park in north Texas died on Friday when she fell from a ride that is billed as the tallest steel-hybrid coaster in the world.

The accident happened just after 6.30pm on Friday at Six Flags Over Texas in Arlington. Park spokeswoman Sharon Parker confirmed that a woman died while riding the Texas Giant rollercoaster but did not specify how she was killed. However witnesses told local media outlets that the woman fell.

"She goes up like this. Then when it drops to come down, that's when it [the safety bar] released and she just tumbled," said Carmen Brown of Arlington. Brown said she had been waiting in line to get on the ride when the accident happened.

Six Flags expressed sadness over the death and said it was temporarily closing the section of the park around the accident site. It did not say how long the area would be closed. "Our thoughts and prayers are with the family and friends during this difficult time," the park's statement said.

The Texas Giant reaches 14 storeys high and has a drop of 79 degrees and a bank of 95 degrees. It can carry up to 24 riders. The ride first opened in 1990 as an all-wooden coaster and underwent a $10m renovation in 2010 to install steel-hybrid rails before reopening in 2011.

Brown said she was next in line behind the woman and saw her being strapped into her seat next to her son. "We heard her screaming. We were like, 'Did she just fall?'" Brown said.

In another amusement park accident on Friday a boat on an Ohio thrill ride rolled backwards down a hill and flipped over in water when the ride malfunctioned, injuring all seven people on it. Operators stopped the Shoot the Rapids water ride after the accident, which occurred on the ride's first hill, said the Cedar Point amusement park in Sandusky, Ohio, said.

In 1999 a 28-year-old Arkansas woman drowned and 10 other passengers were injured when a raft-like boat on the Roaring Rapids ride at Six Flags overturned in two to three feet of water.

Six Flags Over Texas opened in 1961 as the first amusement park in the Six Flags system. It is 17 miles west of downtown Dallas.