CALGARY - Calgary police investigating the disappearance of a five-year-old boy and his grandparents say there was a violent incident in the home where the three were last seen five days ago.
Homicide unit Staff-Sgt. Doug Andrus said police found forensic evidence at the grandparents' home, but wouldn't say what it was.
"Based on what we saw at the scene we believe there was a violent incident inside the residence," Andrus said at a news conference Friday.
"We've sent the exhibits away and we will have a better understanding of that once we get the results back from those exhibits, but based on the evidence, I would say that somebody would be in medical distress."
Nathan O'Brien and his grandparents Alvin and Kathy Liknes were reported missing Monday morning by the boy's mother.
The boy had been at his grandparents' on a sleepover after the couple held an estate sale at their Calgary home on the weekend.
Nathan's parents appeared in front of reporters and cameras earlier this week and made a tearful plea for the return of the three. Rod O'Brien urged his son to be a superhero and stay strong.
Police initially said evidence in the home suggested that its residents didn't leave voluntarily and their vehicles were all accounted for.
Andrus added Friday there were no signs of forced entry at the house. He said police still don't have a motive for what took place.
Officers are still treating the case as a missing persons investigation, Andrus said, and the Amber Alert that was declared Monday remains in effect.
"I can't go into details about what we found in the residence," he said. "We are continuing to assess that information and we are still hopeful we will find these individuals alive."
Police are looking for the driver of a pickup that was noticed several times in the area on Sunday night when the three were last seen.
A picture of the truck captured on closed-circuit video shows a late 80s or early 90s green Ford F-150 in very good condition.
Police aren't calling the driver of the truck a suspect, but believe they may have more information about the missing people.
Investigators put out a call to the more than 200 people they believe went to the sale at the Liknes' home over the weekend.
The pair were selling their things in preparation for a move to Edmonton and then on to Mexico.
Andrus said officers spoke with about 75 people from the sale on Thursday but hope to talk to more.
They've also received hundreds of tips in the case from people across the country in the past few days. Andrus said investigators are working with other police agencies in Canada and abroad.
Officers have several theories as to what might have happened to the three missing family members, but Andrus said he can't reveal what those might be. He said it is an unusual case.
"We still have a lot of work to do and we have a lot of unanswered questions."
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