In this December, 2018 photo released by the Stemberger family, Victor and his wife Han Stemberger, are shown at their home in Centreville, Va.

WASHINGTON — Victor Stemberger wasn’t about to ignore the emails inviting him into a multimillion-dollar business opportunity, so he pitched himself as perfect for the job. In a way he was — but for all the wrong reasons.

The 76-year-old Virginia man, whose family says he has cognitive issues, accepted the offer and boasted of his credentials as “an experienced businessman who does what he says he will do, and executes flawlessly, according to plan.”

He apparently did follow the plan, but the execution wasn’t flawless.

Today Stemberger sits in a Spanish jail, one year after flying into the country with more than 5 pounds of cocaine expertly sewn into bubble jackets in a bag. His family says he knew nothing about the drugs. Though Spanish authorities are dubious, the U.S. Justice Department has advised Spain that it believes Stemberger was duped into acting as a drug mule for a West Africa criminal network, and has asked the country for evidence it’s gathered, according to correspondence obtained by The Associated Press.

Federal officials have for years warned about scams that lure elderly Americans or those with diminished mental capacity — Stemberger had a significant brain injury nearly 15 years ago — into becoming drug couriers. The frauds work by persuading victims they’ll receive payouts if they travel or take some other requested action. The Department of Homeland Security said in 2016 that immigration and border authorities had worked with foreign partners to intercept dozens of unwitting couriers and that more than 30 were believed to still be jailed overseas.

“One of the common characteristics that we find in these scams is that oftentimes the senior is living alone, has lost a spouse and is lonely,” said Sen. Susan Collins, R-Maine, who leads the Senate Special Committee on Aging and helped secure the release of a Maine man jailed in Spain under similar circumstances as Stemberger.

The Drug Enforcement Administration and prosecutors from the Southern District of New York are investigating whether his contacts were part of a West Africa network of money launderers, fraudsters and drug traffickers under scrutiny for scheming the elderly and feeble, according to a Justice Department document sent to Spain last October. It also seeks permission to interview Stemberger, in additions to copies of investigative documents related to his arrest.

Emails reviewed by AP show Stemberger at times sought reassurance the project was legitimate but also portrayed himself as game for it, saying he could travel provided his expenses were covered “and we have a clear plan in place before I depart.”

Retired DEA agent Robert Zachariasiewicz, whose investigative firm has worked on the case, said the 161 pages of emails he’s reviewed make clear that “he’s completely unwitting.”

“It was very hard to read, quite honestly, because it tells a sad tale in and of itself,” he added.

A Vietnam veteran with two master’s degrees, Stemberger specialized in corporate executive coaching and prided himself on being a savvy businessman, his son said. But he hasn’t been the same since a 2006 brain aneurysm left him with impairments in judgment and critical thinking.

Last July, he traveled to Brazil on a trip that was to take him to Spain and on to Asia. His contacts told him the officials he was supposed to be meet with would be visiting his Sao Paolo hotel room to help transfer gifts into luggage.

Stemberger reassured his son over email the work was legitimate: “Gifts referred to in the message are standard protocol for dealing with government officials in this part of the world. No contraband — be sure of that.”

He was arrested the next day on a stopover in Madrid.