WASHINGTON — Donald Trump Jr. had multiple online conversations during the 2016 presidential campaign with WikiLeaks, the anti-secrecy group that last year released a hacked trove of Democrats’ emails, according to four congressional officials.

Mr. Trump, the president’s son, in recent weeks handed over Twitter messages he exchanged with WikiLeaks to several congressional committees investigating Russia’s attempts to disrupt the election, according to the officials. In September, Mr. Trump acknowledged in a closed-door interview with the Senate Judiciary Committee that he had corresponded with the group during the campaign, the officials said.

The correspondence, which began weeks before the Nov. 8, 2016, election and continued through much of this year, is the second time it has been publicly revealed that Mr. Trump communicated with people and organizations with ties to the Russian government who were trying to undermine the presidential campaign of Hillary Clinton.

In July, The New York Times reported that Mr. Trump met with Russians in June 2016 who said they had damaging information on Mrs. Clinton, and that the information was part of the Russian government’s support for Mr. Trump.