One of the bodies of six men killed in a Surrey highrise is taken away by coroners' personnel in October 2007. (CBC)

The parents of an innocent bystander killed in what police have said was a gang hit have launched a lawsuit against one convicted man and two other men awaiting murder charges in the case.

Eileen and Sunil Mohan filed the B.C. Supreme Court lawsuit Friday just days before the second anniversary of the death of Chris Mohan, 22.

Mohan's was one of six bodies discovered in a highrise apartment building in Surrey, B.C., in October 2007, in what's become known as the "Surrey Six" killings.

The body of Ed Schellenberg, 55, a fireplace repairman, was found in the suite and police believe he, too, was inadvertently caught in the gang slaying.

Cory Lal, 21, Edward Narong, 22, and brothers Michael Bartolomeo, 26, and Ryan Bartolomeo. 19, were also found dead in the apartment.

In April, police charged Matthew Johnson and Cody Haevischer with six counts each of first-degree murder and one count of conspiracy.

Jamie Bacon was charged with one count of first-degree murder.

Eileen Mohan, mother of Chris Mohan, is suing those involved in her son's murder, along with the condominium council in the building where he was killed. (CBC)

One month later, Michael Le was charged with one count of first-degree murder and conspiracy to murder.

Their co-accused, 27-year-old Dennis Karbovanec, pleaded guilty to three counts of second-degree murder in the deaths of Mohan, Lal and Ryan Bartolomeo.

He was given a life sentence with no chance of applying for parole for 15 years.

Details from Karbovanec's sentencing hearing remain under a publication ban.

The civil court lawsuit alleges Karbovanec, Haevischer and Johnson were all in the business of selling illegal drugs and went to Lal's 15th-floor apartment with the intention to murder Lal.

"The plaintiffs allege that the murder, or 'hit', was ordered by defendants James Kyle Bacon, Quang Vinh (Michael) Le and one or more individuals whose names are presently unknown."

The statement of claim says that while the men were killing Lal, Chris Mohan left the family's apartment next door to attend a basketball game and "inadvertently witnessed" one or more of the defendants engaged in the murder of Lal.

"The plaintiffs further alleged that the defendants Bacon, Le and Doe ordered the killing of any witnesses to the murder of Mr. Lal so that the murderers would not be identified."

"The defendants, Karbovanec, Haevischer and Johnston, then jointly decided to kill Christopher Mohan to prevent Mr. Mohan from being able to identify them," the lawsuit states.

The lawsuit also names Cory Lal, who lived in the apartment and was murdered along with Mohan, the condominium strata council, the property management company and the owners of the apartment where the murders took place.

The couple is seeking general and punitive damages and legal fees.

No trial date has been set for the remaining accused and a trial isn't expected until early 2011.

Three of the four defendants will be in court next month to ask that the provincial government pay for their legal costs.

No statement of defence has been filed yet.

The statement of claim contains allegations not yet proven in court.