MADRID -- A stampede in an arena where thousands of people were attending a Halloween party killed three women and critically injured two on Thursday, officials said.
It happened just after 4 a.m. in a passageway within the venue leading to the central concert area at Madrid Arena, where the disco-style party was under way.
Someone set off a flare or a firework, causing the stampede that trampled the five young women, said Deputy Mayor Miguel Angel Villanueva.
Thousands of people were attending the party when the stampede occurred, leaving the victims with trauma injuries or breathing and heart failure, said emergency services spokesman Fernando Prado.
Villanueva said the venue's maximum capacity of 10,600 people had not been exceeded and that authorities decided not to evacuate the arena when the accident occurred. Most partygoers were not aware of the stampede because it was confined to the passage, he said.
Halloween has recently become a popular festivity in Spain, coinciding with the traditional feast of All Saints.