WASHINGTON (AP) — Federal regulators have sharpened their antitrust attack against Facebook. They are alleging in a revised complaint that the social network giant pursued a laser-focused strategy to “buy or bury” innovative rivals to suppress competition. It is the second try by the Federal Trade Commission. A federal judge in June dismissed antitrust lawsuits brought against Facebook by the agency and a broad coalition of state attorneys general that came amid multiplying efforts by federal and state regulators to rein in tech titans’ market power. The new complaint lays out a detailed history of Facebook’s conduct, especially since the advent of mobile networks.