A network of companies operated by a secretive Chinese tech firm has been trying to recruit recently laid-off U.S. government workers, according to job ads and a researcher who uncovered the campaign.

Max Lesser, a senior analyst on emerging threats with the Washington-based think tank Foundation for Defense of Democracies, said some companies placing recruitment ads were "part of a broader network of fake consulting and headhunting firms targeting former government employees and AI researchers."

Little information is publicly available on the four consultancies and recruitment companies allegedly involved in the network, which in some cases shared overlapping websites, were hosted on the same server, or had other digital links, according to investigations including Lesser's research.