The bodies of 54-year-old Brett Lietz and 40-year-old Nicole Brochu were found by police early Wednesday on the same road where two other bodies were also dumped recently.
Police say Leitz had no criminal record, but Brochu did between 1989 and 2003, and both were also likely shot where their bodies were found.
They expect an autopsy will confirm the apparent cause of death for the victims who were roommates, but the motive for the killings remains unknown.
Police say evidence supports the theory the deaths are not connected to the two earlier killings.
Since the start of 2013, B.C.'s fastest-growing city has recorded eight murders, which is more than double the rate for Vancouver.