A Hong Kong journalist and former University of Minnesota student was detained over the weekend in Thailand after he was found carrying body armor at an airport.

Hok Chun "Anthony" Kwan, who was assigned by Initium Media Technology to cover the aftermath of last week's bombing at the Erawan Shrine in central Bangkok, was stopped at the Suvarnabhumi Airport on Sunday when authorities found a flak jacket and helmet in his carry-on luggage before he was to board a flight to Hong Kong.

Kwan is being charged with possessing an illegal weapon, which could mean a prison sentence of up to five years. Bullet-resistant jackets are considered military equipment in Thailand, where carriers must have a license. But the law is seldom enforced and journalists have openly worn body armor during recent political turmoil in the country.

The Bangkok bombing left 20 people dead and more than 120 injured.

According to a statement from Initium Media, Kwan was released on bail after a hearing Monday, but he is not allowed to leave Thailand. The company has hired legal counsel to represent Kwan.

"Body armor and helmets used by journalists are not offensive weapons and should not be treated as such," said the Foreign Correspondents' Club of Thailand (FCCT) in a statement Monday about Kwan's arrest.

The FCCT urged authorities to drop the criminal case against Kwan.

According to Kwan's website, he was born and raised in Hong Kong and moved to the United States in 2003.

In 2011, while studying engineering at the University of Minnesota, Kwan joined the student newspaper, the Minnesota Daily, as a staff photographer.

"What began as a casual interest grew into an all-consuming passion and eventually led Kwan to abandon his engineering career and become a professional freelance photographer," Kwan said, on his site.

Kwan's photographs have been published in print and online for the Daily, American Public Media, Minnesota Public Radio and the Associated Press.