More than a week after billionaire couple Barry and Honey Sherman were found dead in their Toronto mansion, police are still searching the sprawling property.

“Because they’ve been here for this long, what it suggests to me is that the couple were found by the swimming pool, well, I don’t think that’s the only crime scene,” CP24 crime specialist Steve Ryan said on Wednesday. “So they’re processing other scenes in other rooms in this big house, and this is why it’s taking as long as it is.”

The pharmaceuticals magnate and his wife were found dead on Dec. 15. Reportedly discovered hanging side-by-side near their indoor swimming pool, police later determined that their cause of death was “ligature neck compression,” or strangulation. While homicide detectives have since taken the lead in the case, police are still calling it a “suspicious death investigation.” Investigators continue to say that they are not searching for any suspects.

In addition to combing through the 12,000 square foot home, police also canvassed neighbours this week for information and surveillance footage. On Thursday, the same day that a large memorial service was held for the couple, police were also seen towing a champagne-coloured Lexus SUV from the property. Neighbours told CTV Toronto that it was the vehicle that Honey would drive.

“It suggests one of two things,” Ryan told CTV Toronto on Thursday. “That they had new information that just came to light and they’ve seized the vehicle. Or, they’re just doing their due diligence and not knowing what they’re looking for, but they’re seizing the vehicle anyway and just making sure that there’s nothing there that they missed.”

On Thursday, a Toronto Fire Services truck also came to the property so investigators could get a view of the mansion’s roof with the help of an aerial ladder. On Saturday morning, police could be seen searching the sewers near the couple’s home, which is still sealed off with police tape.

It was also revealed on Thursday that the Shermans’ family is seeking an independent investigation into the deaths with the help of prominent Toronto lawyer Brian Greenspan, who knew the couple. Early media reports suggested that police were initially looking at the case as a murder-suicide -- something that the Sherman family has vehemently rejected. The family is also seeking a second autopsy.

Ryan, who spent nearly thirty years with the Toronto police, including more than a dozen with the force’s Homicide Unit, said he’s never seen an investigation like this take so long.

“I just think they’re being very, very careful,” Ryan added on Thursday. “They want to make sure they haven’t missed anything.”

With files from CTV Toronto