BEIJING, CHINA — Chinese website operators who include on their sites material classed by the government as “harmful” have been put on notice: Moving their sites to foreign servers will not protect them.In the latest round of arrests of people associated with online smut, authorities expanded their nets to detain anyone who lives in or visits the country, regardless from where their websites are served.

Porn designed to be viewed on mobile devices also was targeted.

According to police, the owners of two websites hosted on U.S. servers and updated via an encrypted virtual private network were arrested Sunday after authorities breached their security protocols. In addition, officials arrested two people accused of selling U.S.-based proxy services to those suspected of attempting to evade Chinese law by accessing forbidden content via “anonymized” networks.

Other arrests included “multiple” staff members of a Chinese company accused of creating more than 40 sites designed to be accessed by mobile devices. According to the official news agency Xinhua, the company collected more than 1 million yuan (about U.S. $150,000) in advertising revenue from the sites.

Since China in January announced a crackdown on “inappropriate” Web content, law enforcement agencies have closed thousands of websites and arrested dozens of people. The cleanup effort, which excludes scientific researchers and health professionals, is thought to be part of a plan to sanitize the country before this fall’s 60th anniversary celebration of the founding of the People’s Republic.