Chinese regulators have halted live streaming on Sina Weibo, one of China’s most popular social media sites, and two other platforms with immediate effect. The sites are accused of being platforms for non-conformist political views.

The order from the State Administration for Press Publication Radio Film and Television posted on Thursday evening required the closure of site without appropriate licenses. Other companies affected by the latest round of restrictions include Phoenix Television’s ifeng.com and AcFun.

The SAPPRFT notice said the three were being punished for carrying “rule-breaking” content on political and social issues and commentaries that advocated negative voices. They were ordered to undergo rectification and help create a cleaner cyberspace. Weibo was granted a license in 2014, but it was suspended after allegedly being used to spread pornography such as live chats with scantily clad women.

Weibo said that it had become aware of the notice. “(SAPPRFT) had recently requested the local competent authorities to take measures to suspend several companies’ video and audio services due to their lacking of an internet audio/video program transmission license and posting of certain commentary programs with content in violation of government regulations on their sites, and Weibo is named as one of these companies,” it said in a regulatory filing.

“The company is communicating with the relevant government authorities to understand the scope of the notice. It intends to fully cooperate with the relevant authorities. The company will also evaluate the impact of this notice on its operations and its administrative options.”

The move is the latest in a series of official actions designed to regulate the fast-growing live streaming sector. Live streaming allows companies and individuals to escape censorship restrictions which apply to all other sections of the Chinese media.

In May, five operators including both Sina, ifeng, and Tencent, were ordered to halt live broadcast of news content. They were said to be in breach of news industry regulations. This month the Cyberspace Administration of China ordered the closure of numerous sites, including that of Harpers Bazaar, hosted on Tencent’s popular Wechat social media platform.