News website 21cbh.com, which is suspected of extortion, had all its website qualifications revoked on Friday, with all of its staff dismissed and the company name deactivated, according to Xinhua News Agency.

The website was run by Guangzhou-based 21st Century Media Co, which claimed to be "the largest professional media operator in the Chinese financial and business media industry".

The move follows a criminal investigation into 21cbh by police, which was announced on Thursday.

Eight people, including the president and editor-in-chief of 21cbh, as well as heads of two PR firms, were detained by police in Shanghai earlier this month. They were suspected of having extorted hundreds of millions of yuan from more than 100 companies since November 2013, using threats of bad publicity.