A more senior South Yorkshire police officer than Ch Supt David Duckenfield was at Hillsborough when 96 people were killed in a crush at the 1989 FA Cup semi-final and would have been expected to take control, another former officer has told a court.

Malcolm Edmundson, a chief inspector in the South Yorkshire police central operations room on 15 April 1989, said he thought Walter Jackson, then an assistant chief constable (ACC), would have stepped in once it became clear that a major incident was taking place.

Edmundson was giving evidence at Preston crown court in the prosecution of Duckenfield, the match commander at the semi-final between Liverpool and Nottingham Forest, who is charged with gross negligence manslaughter in relation to 95 of the people who died.

Questioned by Duckenfield’s barrister, Ben Myers QC, Edmundson, who was marshalling the police central radio system in Sheffield that day, acknowledged that Jackson, as an ACC, had to give authorisation for an “operation support” order – a response to major public disorder.

That order was given at 3.09pm, the court heard, authorised by Jackson, who Edmundson said was in the police control box at Hillsborough. Before that, at 3.03pm as people had begun to emerge from the central “pens” of the Leppings Lane terraces at Hillsborough, a call had been made for dog handlers, also a response to a perceived public disorder problem.

At 3.07pm a request was made from the Hillsborough police control room for a fleet of ambulances to be sent to the ground, and information was given that there were “a lot of casualties”.

Edmundson was asked by Myers if it would have been expected in those circumstances that an officer of Jackson’s rank would get involved. “Yes,” Edmundson replied. “I would have expected the assistant chief constable to take immediate charge.”

Edmundson agreed with Myers that although Jackson was there in the police control room, he never spoke on the radio or gave an order, or took control of what was happening. He said an ACC was never off duty and it did not matter whether he was wearing his police uniform or not.

“Would it be expected that an assistant chief constable would step in if capable of doing so?” Myers asked. “Yes,” Edmundson replied.

Richard Matthews QC, the lead prosecution barrister, re-examined Edmundson following Myers’ questions and asked him if he had any “particular experience, expertise or knowledge” of when somebody would take over from a match commander.

Edmundson said he would expect the senior officer to take over when he understood the seriousness of an incident and if it was “the most serious event in a policeman’s career”.

Edmundson acknowledged questioning from Matthews that he had never been a football match commander, and said was not giving that opinion from his experience of being in command himself.

Earlier in the proceedings, Stephen Ellis, a former police officer, broke down as he recalled that his initial reaction after a large exit gate was opened to ease the crush outside the ground was relief.

The jury has heard that the 24,000 people with tickets to support Liverpool had to get through 23 turnstiles at the Leppings Lane end, and the 10,100 people with tickets to stand were allocated just seven of those turnstiles.

After a large crowd of people built up at those turnstiles, Ellis said, he climbed on top of a police Land Rover and began to shout through a megaphone, urging people to move back from the crush.

Ellis told the court he had not been aware that the wide exit gate C had been opened to allow a large number of people through at once. The jury has heard expert evidence that 2,603 people entered during two openings of gate C. A tunnel leading to the terrace’s central pens was not closed, many incoming people went down the tunnel and the lethal crush took place in the central pens 3 and 4.

Asked about the thinning of the crowd that followed the gate opening, Ellis broke down in distress. He said: “This part upsets me, because I was so concerned about the safety of people in front of Leppings Lane … And then, [in] what seemed like seconds, I looked again and there was just about five metres of spectators in front of the turnstiles. And I felt a huge sense of relief. But where had they gone? God they went in there quick.”

Ellis was excused by the judge, Sir Peter Openshaw, from giving further evidence. Instead, after a lunch break, Myers read extracts from statements Ellis made in 1989 and in 2015. The 1989 statement included observations that Liverpool supporters had been drinking before the match, were pushing and “gripped by a mania” to get into the match, that some dived over the turnstiles and that the police were powerless to control the numbers of people.

Duckenfield is on trial alongside Graham Mackrell, the former Sheffield Wednesday club secretary and safety officer, who is charged with two criminal breaches of safety legislation. Both men have pleaded not guilty to the charges.

The trial continues.