A 51-year-old Tianjin woman was given three and a half years in jail when police discovered the guns used at her balloon-shooting stall were powerful enough to meet the strict legal definition of a firearm, thepaper.cn reported Sunday.
Along with 13 other stall owners, Zhao Chunhua was arrested on October 12 and told she would be released a few days later after the guns were tested.
China defines any gun that is able to fire bullets with a force of over 1.8 joules per square centimeter as an illegal firearm, the paper.cn reported.
"My mother had no idea the imitation guns that we often see at the stalls could be classed as firearms," Zhao's daughter told the media. Zhao has since appealed her conviction.
Living with her daughter in a 600 yuan ($87) per month room near a disused factory, single mother Zhao made 3,000 yuan per month at her balloon stall.
The case has added fire to an ongoing controversy about the nation's gun laws and experts are urging the amendment of the rules on imitation guns.
Netizens vented their frustrations with the law online, with many wondering whether their kitchen implements should be seen as deadly weapons.
However, some netizens argued that strict regulation is necessary and the problem lies in people's lack of understanding of the rules.
China has seen many landing themselves in hot water for buying replica guns or using guns that are considered toys in other parts of the world but are seen as deadly weapons in China.
There have been 23 similar cases nationwide that have led to three balloon-stall owners being convicted, 17 given convictions with reprieves and three imprisoned.