According to an article in the Phnom Penh Post, Walker vanished after leaving his room at an upscale hotel in the Siem Reap province in order to let a housekeeper clean it. He was carrying only a water bottle, leaving behind his cellphone, laptop, passport and belongings.
Walker had been living in Siem Reap for four months and was well known in the neighbourhood, according to colleague Peter Vronsky, who's been co-ordinating search efforts out of Toronto.
"It's very unusual, even for Cambodia, for someone to vanish in that way," he said.
When Vronsky learned of his friend's disappearance, he notified members of Walker's family in Edmonton, who set up a Facebook group called Help Find Dave Walker to try to locate him.
Vronsky said he is worried about key pieces of evidence friend and family have been unable to get access to, which could point searchers in the right direction.
"The biggest thing we’re trying to figure out is what happened to Dave’s laptop and cellphone," he said. "We’re not sure where they are.”
Vronsky is also worried that officials aren't expending enough energy looking into this case, that Walker's disappearance could be painted as just another middle-aged, white guy in southeast Asia "looking for love" and that "the embassy's not going to take this seriously."
A spokesperson from the office of the Minister of State for Foreign Affairs and Consular Services said that Canadian officials have been in touch with local authorities to try to gather more information.
In lieu of a Canadian outpost, the Australian Embassy in Phnom Penh is investigating Walker's disappearance.
Walker is a co-founder of Animist Farm Films, a company based in Siem Reap, which produces "realistically budgeted, high-concept, human interest films," according to its website. Vronsky said Walker had been working on a film relating to the Khmer Rouge, also known as the Communist Party of Kampuchea.
While the Khmer Rouge was in power in the late 1970s, the party introduced policies that disregarded human life and produced repression and massacres on a massive scale.
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