(Adds details from report, background on Google antitrust probe report; updates shares)
June 3 (Reuters) - The Federal Trade Commission (FTC) has secured the right to examine how Facebook Inc's practices affect digital competition, the Wall Street Journal reported on Monday.
Shares of the social media giant extended losses and were down nearly 9% in midday trading.
The FTC's move is part of an agreement that allowed the U.S. Justice Department to take the reins in a Google probe, the WSJ report https://on.wsj.com/2XvgaEl said, citing people familiar with the matter.
Reuters and other media reported on Friday that the U.S. Justice Department may investigate Alphabet Inc's Google to determine whether the technology company violated laws to ensure fair competition.
Shares of Alphabet fell as much as 7% on Monday, losing $54 billion in market capitalization as its shares recorded their biggest drop outside earnings since April 2011.
The news on Facebook underscores a growing U.S. backlash aimed at Silicon Valley companies, and marks another big step by the Trump administration to regulate the biggest tech and social media companies.
U.S. antitrust regulators have divided oversight of Amazon.com Inc and Google, putting Amazon under the watch of the FTC and Google under the Justice Department, the Washington Post reported on Saturday.
Facebook did not immediately respond to a request for comment, while the FTC declined to comment. (Reporting by Arjun Panchadar in Bengaluru Editing by Saumyadeb Chakrabarty and Maju Samuel)