VANCOUVER -- The execution of six people, including two innocent bystanders, in Surrey, B.C., began as a hit on one rival in the province's violent drug trade, but five more were added to the bloodshed to ensure there were no witnesses, the Crown alleged Monday at the start of a sensational gang trial.

For the first time, prosecutors outlined what they allege happened in a 15th-floor condo on the afternoon of Oct. 19, 2007.

Later that day, the bloodied, bullet-ridden bodies of six people were discovered inside the unit, marking the deadliest killing in what was an escalating gang war. The case, which has been dubbed the "Surrey Six" case by local media, has come to symbolize the carnage wrought by gang violence that continued for another two years.

Four of the victims were linked to the region's drug trade, but two were not: Chris Mohan, 22, who lived in the building with his parents and fireplace repairman Ed Schellenberg, 55, had the tragic misfortune to stumble upon the scene at precisely the wrong moment.

Matthew Johnston, Cory Haevischer and Quang Vinh Thang (Michael) Le are now on trial for various murder and conspiracy charges, while a co-accused has already pleaded guilty and another, notorious gang leader Jamie Bacon, is scheduled for trial next year.

Crown counsel Mark Levitz said the three men on trial were associated with the Red Scorpions gang, led by Le and Bacon, who had earlier attempted to extort $100,000 from Corey Lal, a rival in the drug trade.

When Lal missed a deadline to pay, Levitz said, the Red Scorpions plotted to kill Lal.

"The Crown anticipates establishing that the accused and their fellow conspirators ... killed and conspired to kill Corey Lal, and they did so to advance their drug trafficking business by eliminating a drug rival operating in the same area and also to send a message to the drug world that they were not to be defied," said Levitz.

Johnston, Haevischer and another person, who can't be named because of a publication ban, were tasked with taking out Lal, Levitz said. The plan was to target Lal at a condo unit in Balmoral Tower, which he used as a "stash house" for drugs and money, said Levitz.

In the hours before the killing, Johnston met a Red Scorpions associate at Lal's apartment complex, said Levitz. The unnamed associate lived in the same building and provided Johnston with the electronic fob needed to get inside, the Crown said.

Johnston and the third person involved in the killing then met at a nearby Korean restaurant, where the third man was handed a handgun that would later be used in the killing, said Levitz. From there, they went to pick up Haevischer at his apartment, a short drive away from the Balmoral, said Levitz.

Witnesses saw a vehicle that matched the description of Haevischer's BMW drive into the Balmoral's underground parkade, said Levitz, where they used the fob to gain entrance to the building.

Once inside Lal's unit, the trio found four people with ties to the drug world: Lal, Lal's brother Michael, Edward Narong and Ryan Bartolomeo.

The Crown has yet to outline precisely how Mohan and Schellenberg were dragged into the plot, though at some point they found themselves inside, as well.

The Lal brothers, Narong, Bartolomeo, Mohan and Schellenberg were divided into two groups of three, said Levitz. Their heads were covered and they were each shot multiple times, with most of the bullets -- 19 fired in all -- targeting their heads and necks, said Levitz.

The court was shown two photographs of the victims, still lying on the apartment floor. Michael Lal was found lying on his back, while the other five were face-down when they were discovered.

"The accused Johnston and Haevischer, together with (the third man), murdered them to ensure there would be no witnesses to the crime," Levitz said, explaining why six people were killed, rather than just Corey Lal.

Family members of the victims were in court for the opening of the trial, including Mohan's mother, Eileen, who later said she quickly turned away after catching a glance of the photograph of her son's body.

"I looked once and then I looked away," she said outside court, struggling at times to speak through tears.

"I want to remember my son the way he was, not in this state, in blood and amongst strangers he never knew and people who he never should have died with. The most difficult part of it was this."

The trial opened in a crowded courtroom, where dozens of witnesses sat after passing through airport-style security. The trial is taking place in a secure courtroom that was also used for the Air India bombing trial.

The case is expected to last a year, as a judge hears from a long list of witnesses, including gang members, undercover police officers and a police agent. The trial will also see video surveillance and cellphone evidence that document the movements of the accused before and after the murders, said Levitz.

Levitz said the court will hear that Johnston, Haevischer and Le each admitted involvement in the killings.

He said Johnston and Le admitted involvement during an undercover operation in 2008, though he said the exact details of the supposed admission will have to wait until later in the trial. Levitz did not explain the circumstances of Haevischer's apparent admission, which he said occurred shortly after the killings and also involved Johnston.

The murders happened in the early days of what would grow into a full-scale gang war that endured for another two years. In the months following the murders, 10 people were killed in shootings. In one particularly deadly month in early 2009, there were 31 shootings, 12 of them fatal.

Jamie Bacon has been charged with first-degree murder in the death of Corey Lal, and -- with Haevischer, Johnston, and Le -- conspiracy to commit murder in Lal's death.

Haevischer and Johnston each face six counts of first-degree murder and one count of conspiracy. Le faces one count of first-degree murder and one count of conspiracy.

The three men pleaded not guilty to the charges as the trial started Monday.