Cameraman Martin Bouffard just happened to be outside the Metropolis, waiting to see if he could capture footage of Pauline Marois leaving her victory party, when he heard what sounded like fireworks, the court in the Richard Bain murder trial heard on Wednesday.

"I was watching her speech on the huge screen outside the building and maybe 10 minutes after that I heard a huge sound, like fireworks," Bouffard told the court.

A police officer is seen covering the suspect's mouth with a ski mask, after he shouted "The English are waking up!" The still image was taken from video, filmed by Martin Bouffard after the election night shooting. (CBC)

Bain is accused of first-degree murder in the death of lighting technician Denis Blanchette.

He also faces three charges of attempted murder and charges of arson and possession of an incendiary device for the attack outside the Metropolis club where the Parti Québécois was celebrating its election victory.

On Wednesday, the court heard testimony from Bouffard and watched two clips of video he captured that night.

The cameraman, who works for Radio-Canada/CBC, described how he happened to film the chaotic aftermath of the shooting the evening of Sept. 4, 2012.

He told the jury he saw police officers running towards the back of the nightclub with their guns drawn and he followed them with his camera rolling.

I'm here, there's a fire, there's a suspect on the ground, there's guns. - Martin Bouffard, CBC/Radio-Canada cameraman

"I turned the corner. There's a huge fire in the back. It's pretty chaotic over there."

Bouffard said he was filming the fire, trying to keep the camera steady when he heard people yelling.

"Where is he? Where is he? We have him. We have him," he recalled hearing.

While filming, Bouffard said he called his boss and told them to cut to him live on Radio-Canada's election night show.

"I called my boss, Gabriel, [and said] 'Put me on the air live. Put me on the air.' ... I just said to Gabriel, 'I'm here, there's a fire, there's a suspect on the ground, there's guns.'"

Bouffard added how that, while he's not an expert in guns, he saw a police officer handling what looked like a 9mm gun and an AK-47 near where the suspect was lying on the pavement.

A uniformed police officer detains a suspect, who is lying on the pavement outside the Metropolis theatre following the attack outside the Parti Québécois rally. (CBC)

Richard Bain watches calmly

As the jury watched the video, Bain looked on intently from the right side of the courtroom, with a calm expression,

At one point in the video, two uniformed officers lead a man wearing a blue bathrobe and ski mask towards a police car. As the man approaches the cameras, he yells in French, "The English are waking up!"

One of the officers starts to shush the suspect before he reaches over to move the ski mask so that it covers his mouth.

The man continues to yell, but it's no longer clear what he's saying and he climbs into the police car.

Richard Bain faces six charges, including first-degree murder, in connection with the PQ election night victory shooting in September 2012. (CBC)

Jury hears from officer who made arrest

Earlier on Wednesday, the jury heard from two Quebec provincial police officers, Sergeants Stéphane Champagne and Jean-Marc Rochon.

Champagne, who was on security detail at the Metropolis that night four years ago, testified that he chased down the gunman, at one point staring down the barrel of the gun himself, before tackling the shooter.

"I saw that he had a pistol in his right hand. He was trying to shoot," Champagne told the court on Wednesday.

Champagne told the court that he was inside the nightclub near the stage where Pauline Marois was delivering her victory speech when he heard someone say, through his ear piece, that a shot had been fired.

The jury heard how Champagne rushed backstage and out the back door of the club. There he saw a man standing in a ski mask, wearing what he thought at first was a blue cape.

'He was trying to shoot.' - Sgt. Stéphane Champagne, provincial police officer

"I saw him light a distress flare and throw it," Champagne told the court.

Champagne said he didn't see a gun in the man's hand at first, but he chased him and was ready to tackle him when the man turned suddenly – pointing a gun.

"The barrel was directly pointed towards me," Champagne said, adding that the gunman was about four feet away.

When the gun didn't go off, Champagne forced the gunman down to the ground and handcuffed him with the help of his colleague, Rochon.

At one point during his testimony, Champagne was asked by the Crown if he could identify the individual he chased after that night. He identified the accused.​

The trial began last Thursday and is expected to last between six and eight weeks.