Updated

Thousands of concertgoers trying to enter a stadium to hear old Korean songs sparked a stampede Monday that killed 11 people and injured 72 others, officials said.

The stampede occurred in this city about 165 miles southeast of Seoul (search) as about 20,000 were entering an outdoor sports stadium for a concert organized by a local TV network, said Kim Sung-in, an official with the city government's disaster management division.

The 11 people died when one of the gates opened to let the audience inside, Kim said.

"There were elderly people in the front, and when pushed from behind ... [they] fell, leading to a chain reaction of falling and being crushed," witness Kang Mi-kyung told South Korea's Yonhap news agency.

The dead were eight women aged from 54 to 76, along with three boys aged 7, 12 and 14, another city official said. Another 72 people were injured, said the official, who refused to give his name.

The stadium's capacity was 20,000, Kim said, and the event was canceled after the stampede.

The concert was for a program of Korean songs popular among the elderly, part of a weekly show televised nationally on the MBC network.

"People kept pushing us from behind and I tried not to fall but couldn't help it," said Kwon Kang-sook, 54, who was treated for a stomach injury in the emergency room of Sangju Sungmo Hospital (search).

She said each gate at the stadium had two doors, but that only one had been opened at the gate where the stampede occurred.

One woman said her 66-year-old mother-in-law Kim In-shim — who died in the stampede — had gone to the stadium early to get a front-row seat. "When the door opened, she fell over and was trampled by other people," said Huh Soon-ja, whose father-in-law also broke a leg.

MBC issued a statement expressing condolences to the victims and said it would investigate the accident along with city authorities.

The concert had been scheduled at the end of a three-day bicycle festival organized by the Sangju city government.

The city of 120,000 people claims to have the highest per-capita bicycle ownership in South Korea and was promoting bicycle use to help the environment.

Monday was a national holiday in South Korea, National Founding Day (search), when according to legend the first Korean dynasty came to power more than 4,300 years ago.