The judge investigating the tragedy that occurred at a Halloween party at the Madrid Arena where four girls were crushed by a surging crowd has subpoenaed a city councilman for questioning as a possible defendant.

According to court sources, Pedro Calvo, in his capacity as president of the municipal Madrid Espacios y Congresos company, is the person responsible for contracting with municipal locations for holding events like the Halloween party.

Shortly after the incident, municipal sources told Efe that Calvo presented his resignation from all his posts to capital Mayor Ana Botella.

The judge also subpoenaed businessman Miguel Angel Flores, the manager of event organizer Diviertt, and the representative of security firm Kontrol 34.

The magistrate on Tuesday conducted an inspection in the Madrid Arena pavilion, where the deadly event occurred in the wee hours of Nov. 1.

A police report based on images from security cameras revealed that the number of people attending the party significantly exceeded the venue's allowed capacity of 10,000.

At a certain point, in one of the access passageways a human stampede started, and it was there that the four teenage girls were crushed and a child of 2 - who is still hospitalized - was seriously injured.

Calvo's is the first resignation by a political official amid the controversy over the tragedy. EFE