A pair of Hong Kong journalists behind two political affairs magazines have pleaded guilty to running an illegal business in Shenzhen in a case that underlines the legal risks facing reporters who straddle the border. Publisher Wang Jianmin and editor-in-chief Guo Zhongxiao appeared before Nanshan district court yesterday. Prosecutors said their company National Affairs Limited, registered in Hong Kong, had earned HK$7 million through the publication of two magazines, New-Way Monthly and Multiple Face . READ MORE: Documentary exposes newsroom struggles with censorship while covering Hong Kong's Occupy movement Both are printed in Hong Kong but copies are sent to eight people on the mainland, all friends of the publisher, the defence said. The mainland audience accounted for 66,000 yuan (HK$80,600) of total revenue, less than half the 150,000 yuan minimum needed to raise the offence to the level of running an illegal business. The prosecution wrongly counted Hong Kong revenue as part of the mainland business to make their case, lawyers argued. Wang, 62, and Guo, 40, are Hong Kong ID holders but were living in Shenzhen when arrested in May. They made weekly, sometimes daily, trips across the border. In his statement to the court, Wang said: "The trial was fair and I'm grateful for the [Communist] Party's and the government's education." Guo said: "We published unverified news and have tarnished the image of the party and the government." Guangdong province's print and broadcast regulator said the magazines were "illegal publications" not registered on the mainland but nevertheless sold to local readers. Wang's wife, who helped send copies of the magazines via the post, as well as a freelance contributor from Henan province also pleaded guilty to operating an illegal business before the same court. Sentencing is expected later. Mainland customs is responsible for overseeing the importation of media and regularly stops books or monthlies that touch on political topics. Chen Nansha, the defence for Wang, argued that under "one country, two systems", publications in Hong Kong should be protected by Hong Kong laws, and the two magazines were legal in Hong Kong. Li Daoyan, Guo's lawyer, argued Guo only edited the magazine and was not involved in the business. "If editing a Hong Kong magazine in Shenzhen is a crime, do all journalists on the mainland who work for overseas news organisations face the same risk?" The trial was fair and I'm grateful for the [Communist] Party's and the government's education." Publisher Wang Jianmin Mainland authorities have a range of charges they can use to silence Hong Kong media outfits that attract too much notice. Hong Kong publisher Yiu Man-tin, chief editor of the Morning Bell Press, was sentenced to 10 years in prison last year. Yiu was charged with "smuggling ordinary goods". He had published a book by dissident Yu Jie titled China's Godfather, Xi Jinping . Wang joined Yazhou Zhoukan , a magazine in Hong Kong, in the mid-1990s. He left in 2007 and established New-Way Monthly in 2010 and Multiple Face two years later. Correction: An earlier version of this report misspelled the name of Wang Jianmin's lawyer. It is Chen Nansha, not Chen Naisha.