Spanish police are investigating videos taken by security cameras in a corridor of the Madrid Arena, scene of a giant Halloween party where three people died and two were badly hurt in a stampede.
The videos to be studied will be limited to those at the exact site of the tragedy, which has been "very specifically located", police officials told EFE.
Agents are trying to confirm the hypothesis that the stampede occurred when lighted firecrackers and a flare supposedly panicked a crowd when thrown among them in a packed corridor between the arena's track and a stairway to an upper level.
Police are also interviewing Madrid Arena workers and young people who were at the Halloween party.
The controversy continued Friday about whether the crowd was above the arena's legally permitted capacity, a possibility denied by Divertt S.L., the company that rented the facility, but which has been questioned by some who attended the Halloween party.
The number of people present at the festivities per square meter can be determined by an analysis of the videos, photos and other studies, said the judge presiding over the investigation, Jose Luis Gonzalez Armengol.
The two people who were injured remain in critical, but stable, condition, authorities at the Madrid hospitals where they have been admitted said.