SHIJIAZHUANG - Police in North China's Hebei province have arrested 17 people suspected of involvement in an online arms sales network, Hengshui public security bureau announced Thursday.

All accused of illegally making and selling guns, gun parts and ammunition, the suspects were rounded up in a concerted effort by law enforcers in ten provinces.

The investigation began in May, when a man known only as Zhang was found to have ordered more than 3,000 items which appeared to be gun components -- bolts, triggers and barrels -- from various metalwork shops in Jingxian county. The items were then delivered to other parts of the country by courier. Zhang rented a yard and surrounding bungalows in the county to serve as a warehouse for the illegal goods.

Zhang used Tencent's QQ, a popular online messaging service, to become acquainted with many gun component dealers. He published adverts on the Internet and sold the parts mainly to wholesalers, making more than one million yuan ($156,200). The wholesalers in turn sold the components and ammunition online in over 20 provinces, cities and regions.

Manufacturing and sale of guns is extremely strictly regulated in China to control violent crime. Ordinary private citizens are not allowed to own guns and can be sentenced to up to seven years in prison if convicted of illegally possessing one.

From March to May in 2015, Zhang carried out 145 transactions totaling over 800,000 yuan via his bankcard and Alipay, China's largest online payment provider.

Hengshui police seized eight complete weapons, ten "arms manufacturing devices," some 135,500 bullets, over 9,000 gun components and more than 40 computers and mobile phones. They also confiscated some 500,000 yuan.

The case is still under investigation.