MANILA, Philippines (AP) – President Gloria Macapagal Arroyo ordered a rapid investigation into a stampede that killed at least 74 people and injured more than 500 others at a suburban Manila stadium where about 30,000 people had lined up to watch a popular TV game show.

The crowds were waiting to get inside the Philsports Arena for the show “Wowowee” – which raffles off huge cash prizes – when the stampede occurred Saturday, said Vicente Eusebio, the mayor of suburban Pasig.

He said the melee erupted as the crowd pushed and surged toward the gates, thinking they were open, trampling those in front. One survivor said some people in the crowd became rowdy when they could not enter.

Health Secretary Francisco Duque III said 74 people were killed, including a person who died of massive bleeding more than 12 hours after the stampede, and another 514 were injured. Most of the injured had been sent home, but more than a dozen remained hospitalized with serious injuries such as fractures, severe cuts and contusions, and mental shock, he said.

Arroyo ordered authorities to conduct a thorough investigation and submit a report to her in 72 hours. A government investigative body summoned the host of the show, comedian Willie Revillame, and organizer ABS-CBN for an interview today.

Wowowee is hugely popular in the Philippines. Entry is free, but for Saturday’s first anniversary show only the first 300 were eligible to play games in which they might win up to 1 million pesos in cash or a fully furnished house.

“The gates were being partially opened then shut,” said Myrna Britania, 42, who spoke at a hospital as she awaited news of friends and relatives who had been injured. “The raffle tickets can be obtained at the gate so everyone was in a hurry. There was pushing and people in front of the gate were crushed.”

Britania, who had spent all night in line, said “people at the back of the line were pushing, not knowing there were already people dead lying on the ground in front.”

Eusebio and police denied reports that the stampede was caused by a bomb scare.

Bodies were lined up on the side of a street outside the stadium for identification, as bags and shoes lay scattered outside the hall. They were later moved to two hospital morgues, where officials plastered digital photographs of unidentified bodies on windows.