Afghan soldiers that went missing on Saturday “while chaperoned to the Cape Cod Mall in Hyannis” were caught at the Canadian border. The whereabouts of the men prompted much speculation, but Pentagon official Major Andrew Aranda assured that they were “carefully screened” and did not pose a threat to Americans.

Despite the assurances, a bulletin issued by Joint Base Cape Cod indicated that there was a serious effort to locate the missing men. Fox News reported that they were “caught at the Canadian border,” and further reported that men were “just the latest group of Afghan soldiers to try to melt into the North American population.”

The men were a part of a joint training exercise conducted annually by the Federal Government since 2004, and sponsored this year by US Central Command, in the effort to “promote cooperation and interoperability among forces, build functional capacity, practice peacekeeping operations and enhance readiness.” An excerpt from the report indicates that this is not an unusual occurrence:

“The latest case came just days after two other Afghan military trainees vanished from a Drug Enforcement Administration training program, only to resurface in Buffalo, where they told authorities they’d gone on a sightseeing road trip…”

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Other similar cases were also documented in the Fox News report, and a U.S. official says they happen “frequently.” Perhaps the best way to handle these “frequent” disappearances is to do away with the joint training exercises or at least monitor the participants.

A Fox News report from way back in 2010 discussed AWOL Afghans, reporting that since 2002, “46 Afghans have deserted their armed forces while in the U.S. for language and military training. Of those 46, roughly half–at least 22–have found their way north of the border.” The soldiers were assisted by a “network of people, including Afghans who left Lackland Air Force Base before them; a group of naturalized and undocumented Mexican women in Texas; relatives of current and former Afghan military students living in the West; and at least one Iranian taxi driver who runs a human smuggling business at the Canadian border.”

There was no explanation as to why the senior military officers from Afghanistan left the base in the first place, however Boston.com reported on a man who encountered one of the soldiers while on holiday with is family. The witness said, “He asked us ‘what direction is Canada—and how far of a drive would it be to get there.’”