A “wonderful and well-respected” couple, who were found dead in their Lake Bonavista home by their adult son on Saturday afternoon, were murdered, say Calgary police.

Emergency services initially treated the southeast home where Don Carlson, 59 and Roxanne Carlson, 56, were found dead as possibly being contaminated by carbon monoxide.

Fire crews had to clear the scene before a medical team could enter and it wasn’t until Sunday morning that officials labelled the deaths as suspicious.

Police deemed the deaths a double homicide on Tuesday, after autopsies were completed Monday. Police are not releasing the causes of death.

The Carlsons were parents to three adult children, who are “shocked and devastated by the sudden loss.”

“Both were loving parents and will be terribly missed by all those who knew and loved them. Our parents were wonderful and well-respected people, known for their love of family, involvement in their community, and their professional accomplishments,” reads a statement released on behalf of the Carlson family.

The couple lived in a home in the 12000 block of Lake Erie Road S.E. with one of their adult children, who was not home when their bodies were discovered.

When the Carlson’s son came to the family home on Saturday afternoon to visit his parents, he found them dead, and his call to 911 initially came in as a potential carbon monoxide poisoning.

“It’s a traumatic event to step into a residence and find two persons that have passed away. Carbon monoxide was a thought, that was the first thought. That was quickly ruled out,” said Staff Sgt. Grant Miller of the Calgary Police Services’ homicide unit.

The circumstances surrounding the Carlson’s deaths remains mysterious.

Police have no clear motive as to why the couple were murdered and are not ruling out the possibility that it was a random attack.

“Our investigative team is investigating every thought and every possibility at this time,” said Miller.

“At this point, it’s too early to speculate what the exact motive may be. You ask if this is a random attack, at this moment there is no indication to indicate that but again, it is something we’re looking at, it is something we’re pursuing.”

Miller said investigators are also looking into any connection to the couple’s careers.

Roxanne worked as a psychologist at the Calgary Board of Education and Ron was general manager of Albern Coins & Foreign Exchange on 16th Avenue N.

What was found inside the family’s home, in the affluent community of Lake Bonavista, has formed a large part of the police investigation.

Miller wouldn’t elaborate on what was found inside the home but said police will remain at the house for several days to ensure that forensic investigators have the time they need to conduct a thorough examination of every aspect of the family home.

“It is very early on and as a result of that we won’t be releasing what we have discovered inside the residence in any form,” Miller said.

The Carlsons were last seen at 9:30 p.m. on Valentine’s Day and investigators, and the couple’s children, are asking for the public’s assistance in determining their movements between then and the time they were discovered dead.

“If anyone feels they have any relevant information we would ask them to please contact Calgary Police Services,” says a statement released on behalf of the Carlson family.

The couple’s children are not suspected suspects at this time.

“The family is very devastated, these are great people in a very nice neighbourhood in Calgary,” Miller said.

AKlingbeil@calgaryherald.com

Twitter.com/AnnaliseAK