A pedestrian bridge with dozens of people on it collapsed Saturday afternoon, killing one person and injuring several people, apparently after they rocked the span back and forth, authorities said.

"One of the cables to the bridge snapped. The bridge flipped over and the whole bridge went down into the river," said Polly Burkeen, whose Swinging Bridge Boat Dock sits below the steel suspension bridge over the Little Red River.About 30 to 50 people were on the 50-foot-high, 200- to 300-foot-long bridge, said Cleburne County dispatcher Gary Hooten. However, Bill White, a spokesman for the county sheriff's dispatcher, said he was unsure how many people were on the bridge.

Burkeen said she heard a sound like an explosion. "I looked down that way and there was nothing but smoke and dust," she said.

"They're pulling them out," the dock owner said. "Ambulances are coming and going constantly."

Coroner Dwight Olmstead pronounced a female dead on the scene, said reporter Paul Headden of radio station KAWW in Heber Springs.

Several people were taken to Cleburne County Memorial Hospital, said Carolyn Vinson, a telephone operator there. She said she could not release further information.

Ambulances from three neighboring counties helped take the injured to hospitals, Hooten said.

"At first, there were so many injured, people were taking them to the hospital in personal cars and police cars," he said.

Cranes were brought to lift the wreckage of the bridge and determine if anyone was underneath, White said. A state Forestry Commission bulldozer was brought there, and another was on the way. The National Guard also was asked for assistance.

"We don't know what all we've got," White said.

The person who reported the collapse said people had been rocking the bridge back and forth before, said another sheriff's spokesman.

It is common for people on the bridge to try to rock it, said KAWW Manager Chuck Howell.

The bridge is five miles east southeast of Heber Springs, which is about 60 miles north northeast of Little Rock.

The span has a wooden roadbed and was used by vehicles until 1972, said Burkeen.

"It was kept as a walking bridge," she said. "It was placed on the National Register of Historic Places four years ago."

Many people go to the bridge because of the area's natural beauty, said Heber Springs resident Cathy Stogsdille.

"I fly over the area all the time," White said. "There's always people underneath it fishing."

Burkeen said, "There's nothing left standing but the pylons on the bank."