Read the following article and answer the question. Article: Authorities will continue to take a hard line on Internet-based rumors and punish those creating fake information, a senior official said on Thursday. Authorities have removed more than 210,000 online posts and shut down 42 websites since mid-March in their latest crackdown on online rumors, said Liu Zhengrong, a senior official with the State Internet Information Office. Fake information or rumors spread through the Internet, especially on micro blogs, have harmed social order and residents' daily lives, he said at a news briefing in Beijing. Before the crackdown, six people who allegedly fabricated rumors about "military vehicles entering Beijing" had been detained and 16 websites closed for fake online information, according to police authorities. "What we've done and will do is to make sure residents can know what they want to know, say what they think and supervise our management in a reliable and useful network environment," Liu said. Liu disagreed that the Internet can police itself against rumors, and told China Daily that some netizens can't distinguish truth from fiction, "requiring government departments and website companies to take measures". On Monday, the Internet Society of China posted a proposal calling on Internet companies and websites to strengthen self-discipline and prevent the spread of online rumors. In response, three main Internet companies in the country - Sina, Baidu and Tencent - said they will target fake information with advanced technology and invest in manpower to supervise online information. Zhao Zhiguo, deputy director of the Telecommunications Administration under the Ministry of Industry and Information Technology, said stricter self-management of websites will help banish online rumors. "Internet companies should take legal responsibility when operating their websites. They should not become a hotbed for rumors and provide opportunities for fake information," Zhao said, adding they will launch similar crackdowns to close illegal website companies and punish those... Question: How many websites were shut down before mid-March in the latest crackdown on online rumors? Answer:
16