The bodies of Nathan O'Brien and Alvin and Kathy Liknes have not been recovered since the three disappeared from the couple's Calgary home June 29, but police have laid three murder charges.
The couple had been having an estate sale that weekend as they downsized ahead of a move to Edmonton and then to a residence in Mexico. Nathan was at his grandparents' house for a sleepover.
A police spokeswoman confirmed Tuesday that officers are in Mexico.
"It's just making sure that all the avenues are covered. There's nothing to it other than just crossing t's and dotting the i's," said Calgary police spokeswoman Emma Poole. "We're not going to get into details of how long they've been down there, where they are or how many went."
Douglas Garland, 54, is facing two charges of first-degree murder and one count of second-degree murder.
Garland was initially considered a person of interest in the case and was held on an identity theft charge unrelated to the disappearance of the trio.
Garland had lived for several years in Vancouver using the identity of a dead person. Police alleged he was using that identity again when they brought him in for questioning in the missing persons case.
That charge has now been stayed by the Crown.
Police spent weeks searching Garland's rural residence near Airdrie, Alta., as well as the surrounding fields, bodies of water and properties.
He is scheduled to return to court next week on the murder charges.
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