Sardar Ahmad was born in Afghanistan but got a ticket out of the war-torn country when he was awarded a Fulbright scholarship through the U.S. Embassy in Kabul. Ahmad, now a 43-year-old doctor, moved to the U.S. for his Fulbright before relocating to Canada a decade ago where he finished his residency last year. Recently, Ahmad, who now works in Sarnia, a small Ontario town along the border between Canada and Michigan, got an email that, without warning, announced that his Nexus card had been revoked.

Ahmad was presumably not considered a security risk when he was granted a Nexus card, a Homeland Security program that allows low-risk, “pre-screened travelers expedited processing when entering the United States and Canada.” Ahmad decided to visit the U.S. Customs and Border Protection Office during his lunch break from seeing patients to see what the problem was. So Sardar drove to the nearby border crossing at the Blue Water Bridge on Friday where U.S. officials promptly detained the doctor and Canadian citizen for five hours.

Here’s more on what happened from the Observer:

As soon as he told the U.S. border agent his situation, Ahmad said he was pulled over, had his car keys taken from him and held for questioning for hours—all while his elderly patients who arrange transportation to his Sarnia office in advance waited for him back at his clinic… During his detainment, Ahmad said U.S. border agents asked him what “tribe” he belonged to and the name of his “tribe chief,” whether he had seen “a lot of gunmen” growing up in Afghanistan and specific questions about the family he left behind there… “I was telling (the U.S. border agents), ‘I need to call my clinic to at least cancel the patients,’ and they said, ‘No, you can’t touch the phone,’” Ahmad said, noting a border agent eventually allowed him to call his medical clinic before he was eventually cleared—but declined—to enter the U.S. hours later.

“It was frustrating for me because I was worried, I was scared, I didn’t know what was going to happen next,” Ahmad said Monday. “You never know. They could put you in jail. You could lose your career—everything—all overnight.”