As China prepares for Spring Festival, authorities are cracking down on illegal fireworks sales through social media platforms, warning of serious safety risks.

Last Friday, police in Hangzhou, Zhejiang province, detained a man who had illegally stored 3 metric tons of fireworks in a rented house in Liangzhu village. The man purchased the fireworks from another province, promoted them through WeChat groups and offered home delivery, according to local authorities.

The Hangzhou Public Security Bureau reminded the public that fireworks are classified as dangerous goods, and their sale, transport and storage require permits. Violations will be dealt with strictly, officials said.

The Ministry of Emergency Management emphasized on its official WeChat account that while licensed retailers can post promotional materials online, all transactions must occur in authorized stores. Deliveries to customers are prohibited, even for permit holders.

Retailers whose illegal fireworks sales exceed 50,000 yuan ($6,900) are considered criminal operations under Chinese law.

In Dongying, Shandong province, police arrested a retailer last month for delivering fireworks without a transportation permit. Similarly, in Bozhou, Anhui province, a vendor was detained for 15 days after advertising unlicensed fireworks online and selling them offline.

Licensed vendors must follow strict safety regulations. A fireworks store owner in Hangzhou, identified only by her surname Ye, explained that stores must be located in remote, single-story buildings far from crowds and gas stations.

"Store owners are required to complete online courses and pass two safety exams every two years to maintain their permits," Ye told Tide News, a local media outlet. "Before Spring Festival, local fire, emergency management and police departments inspect stores weekly."

Unlicensed online fireworks sellers have previously profited by offering lower prices and home delivery. However, Ye pointed out that such practices violate regulations.

"Transportation permits are issued for specific vehicles on fixed routes and can only be used once. It's impossible for a store to get a one-time permit for each customer," she said.

Authorities have urged the public to purchase fireworks only from licensed stores. In some areas, including Yuhang district in Hangzhou, officials have published lists of authorized retailers.

Consumers are also advised to inspect product packaging and labels for manufacturer information, certification, warning signs and usage instructions before making purchases.

Xu Nuo contributed to this story.