Jerusalem judges have extended the detention until tomorrow evening of the four people arrested on suspicion of involvement in the collapse of the lighting rig at Mount Herzl on Wednesday, which killed a woman soldier and injured seven others.

The IDF soldier, 2nd Lt. Hila Bezaleli, was killed during rehearsals for this week's major Independence Day ceremony at the national cemetery site.

Initially three suspects were held: Oren Warshavsky, who was said to have been the engineer for the rig; Itzik Zucker, the site's safety manager; and Elad Lavi, the vice president for operations manager of Itzuv Bama, the firm that had been the successful bidder to produce the Independence Day event. All three were ordered released by a magistrate's court judge. However, at the request of the police, the order was stayed to give the police an opportunity to appeal to the district court and explain the relationship among the work of the three at the site. District Court Judge Joseph Shapira ordered the three to remain in custody.

Although Magistrate's Court Judge Haim Li-Ran had initially taken the police to task for acting too quickly to arrest the three, Judge Shapira ruled the action was justified out of concern that the suspects might flee, or that that they could attempt to interfere with the investigation. A fourth suspect, Alex Sela, was arrested on Thursday.

Sela was the producer of the Independence Day ceremony and the request for his continued detention was based on concern that he too could interfere with the investigation.

Police told the court that a number of people remained to be questioned over the fatal accident, including people who are Sela's subordinates. Sela's firm, Sela Productions, has been involved in a number of major events in recent years, including events related to the Jerusalem Marathon, and has done considerable work with the Jerusalem municipality.

Itzuv Bama, which was awarded a contract by the Public Diplomacy and Diaspora Affairs Ministry to produce the Independence Day ceremony itself, had also been considered a leading player in its field and has been involved in organizing major events in Israel and abroad, from official ceremonies to rock concerts.

In the court hearing on Friday, police said they had substantial suspicion of negligence with respect to the planning, construction and supervision of the lighting rig that collapsed. Police superintendent Eli Cohen also said the account of events provided to police by the suspects were at variance with one another. "The engineer [Warshavsky] says he never received the work," Cohen recounted. "The safety adviser [Zucker] contends there was an engineer who was responsible, and the employees of [Itzuv] Bama contend that, from the moment they finished constructing the structure and transferred it to the producer [Sela], the responsibility rests with the organizers of the ceremony."

On Friday, Sela's lawyer, Elad Rath, said his client had expressed concerns about the safety of the structure before the accident, but Sela was then assured that everything was fine. Several minutes before the rig collapsed, one of Sela's representatives on the scene called Sela to express concern over the safety and called Itzuv Bama, but at that point it was too late, the lawyer added.