The Federal Trade Commission on Thursday faced renewed questions about its handling of its antitrust investigation into Google, after documents revealed that an internal report had recommended stronger action.

The 2012 report, from the agency’s bureau of competition, said that the agency should sue the Internet search company for anticompetitive practices, according to several people who saw the report but would speak about it only under the condition of anonymity. At least one other staff report, they said, recommended not to pursue a lawsuit. In early 2013, the agency unanimously voted not to bring charges after an investigation.

Google’s critics and competitors on Thursday jumped on the news, first reported by The Wall Street Journal, arguing that the F.T.C. had failed to take appropriate action. They called on Europe, which is now looking into the company’s practices, to pursue tough regulations.

Yelp, which is a top Google competitor for consumers searching for local businesses, has long accused Google of abusing its dominant search position to elbow out competitors and push its own products instead. On Thursday, Yelp doubled down on those assertions.