10/03/2013 04:50 EDT | Updated 01/23/2014 06:58 EST

Surrey Six trial: police first suspected gas leak

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The trial of three men accused of killing six others in a Surrey apartment building continued today in Vancouver with testimony from the first police officer on the scene.

Cpl. John Hanson said the first officers to arrive wore hazmat suits because they were told it was a gas leak, not a shooting.

- Read about testimony from the gas repairman's nephew

But when he saw a handgun lying next to the six bodies, Hanson testified, he realized it was a crime scene.

The girlfriend Corey Lal, one of the victims, also testified on Thursday morning, saying she suspected he was involved in drugs and had dropped him off at the high-rise before.

Accused plead not guilty

The three men accused of the killings, which took place in a Surrey high-rise in 2007, all pleaded not guilty to first-degree murder charges at the opening of the trial on Monday in B.C. Supreme Court in Vancouver.

Matthew James Johnston and Cody Rae Haevischer are charged with six counts of first-degree murder and Quang Vinh Thang (Michael) Le is facing one charge of first-degree murder.

Two other men charged in the case, Jamie Kyle Bacon and Sophon Sek, will be tried separately at a later date.

Prosecutors say they intend to prove that Johnston and Haevischer went to the apartment to kill victim Corey Lal because he failed to meet a deadline to repay a $100,000 drug debt.

They say the accused killed the other five people in the apartment so there would be no witnesses to the murder of Lal.

Prosecutors said the six bodies were found in two groups of three inside the apartment. A total of 19 shots were fired in the massacre, which took place around 2:40 p.m. PT on Oct. 19, 2007.

The six all had their heads covered and shots were fired directly into the backs of the heads of three of the victims. One other was shot in the back, another in the head, and one in the face and neck.

The three accused were all members of the Red Scorpions gang, the Crown said.

But only two, Johnston and Haevischer, are charged with the first-degree murders of Schellenberg, 55, and Mohan, 22, — whom police have described as bystanders who happened to be in the wrong place at the wrong time.

At the time, Metro Vancouver was in the grips of a violent gang war dominated by a deadly rivalry between the Red Scorpions and the UN gangs.

Four of the victims, Ryan Bartolomeo,19, brothers Michael Lal, 26, and Cory Lal, 21, and Edward Narong, 22, were described by police as having criminal lifestyles.