Special counsel Robert S. Mueller III has convened a criminal grand jury to investigate Russian interference in the 2016 election and is focusing on Donald Trump Jr.'s meeting last year with a Russian lawyer who promised damaging information about Democrats, according to a person familiar with the inquiry.
The impaneling of a new grand jury in Washington indicates that the investigation into alleged links between President Trump's campaign aides and Russian intelligence is entering a new stage that is likely to include calling witnesses to testify under oath, the person said.
Investigators working for Mueller, who was appointed in May, have contacted and received records from several of the eight people who attended a meeting at New York's Trump Tower on June 9, 2016.
In addition to Trump's oldest son, the group included the president's son-in-law and now senior advisor, Jared Kushner; Trump's campaign manager at the time, Paul Manafort; and a Russian lawyer, Natalia Veselnitskaya.
In a rally Thursday night in Huntington, W.Va., the president again denounced what he called the "totally made-up Russia story."
He reiterated his charge that Democrats are stoking the Russia allegations as "just an excuse for the greatest loss in the history of American politics."
"What the prosecutors should be looking at are Hillary Clinton's 33,000 deleted emails," the president said, provoking whoops and chants of "Lock her up." He continued by saying prosecutors should also examine her paid speeches and financial interests.
The House and Senate intelligence committees are investigating Russia's interference in the election and whether there was collusion with Trump's campaign.
Mueller "believes there is a need to impanel a grand jury so he can readily issue subpoenas, gather testimony, and compel individuals to testify regarding what they know about Russian interference in the election, the Trump campaign, and likely a host of financial matters," Sen. Jack Reed (D-R.I.), a member of the Senate Intelligence Committee, said late Thursday.
"These are gravely serious issues," he added.
The Wall Street Journal first reported Thursday that Mueller had convened a grand jury. It wasn't immediately clear if it has taken over from a separate grand jury in northern Virginia that was known to be investigating contacts between Russia and Michael Flynn, who resigned as Trump's national security advisor in February.
Reuters subsequently reported that the new grand jury recently issued subpoenas in connection with Trump Tower meeting.
Convening a grand jury does not mean that Mueller is preparing criminal charges or is even close to doing so. It may indicate he believes it is the proper venue for an expanding investigation that is focusing on several members of Trump's family, as well as current and former aides.
It may also indicate that he believes the Democratic-leaning capital offered a more sympathetic jury pool if he ultimately opts to bring charges. Trump has repeatedly denounced the probe as a witch hunt and accused Mueller and his aides of partisan bias.
The president's lawyer, Ty Cobb, said in a statement released by the White House that he was unaware of a new grand jury.
"Grand jury matters are typically secret," Mr. Cobb said. "The White House favors anything that accelerates the conclusion of his work fairly."
He added, "The White House is committed to fully cooperating with Mr. Mueller."
Cobb's statement also said that former FBI Director James B. Comey, whom Trump fired in May, said three times that the president was not under investigation "and we have no reason to believe that has changed."
Trump has made clear his anger that Atty. Gen. Jeff Sessions recused himself from the Russia investigation in February after it was revealed he had met several times with Russia's ambassador last year.
Rod Rosenstein, the deputy attorney general, then took charge of the inquiry. But shortly after Trump fired Comey for what the president later called "this Russia thing," Rosenstein appointed Mueller to limit the ability of the White House to interfere with the investigation.
Cornell University law professor Jens David Ohlin said the convening of the grand jury indicated that Mueller's inquiry was growing more serious.
"This suggests the investigation will end with indictments," Ohlin said.
"If there was any suggestion that Mueller was going to simply submit a report to Congress and allow the political process to digest his findings, that seems unlikely now," he added. "This is a criminal investigation in the fullest sense of the term."
Prosecutors are seeking to talk to participants at the meeting that Trump Jr. convened after being told that Veselnitskaya was bringing material showing improper donations to the Democratic National Committee that could be useful against Clinton, the Democratic presidential nominee.
According to emails released last month by Trump Jr., the meeting was proposed by Aras Agalarov, a billionaire Azerbaijani real estate developer living in Moscow. The derogatory information from Agalarov was "part of Russia and its government's support for Mr. Trump," according to an email released last month by Trump Jr.
Trump Jr. said that the material Veselnitskaya provided was not helpful and that nothing came of the meeting. But investigators may see the meeting as significant because of the suggestion that it was part of a coordinated effort by Moscow to help Trump.
Also at the meeting was Rinat Akhmetshin, a Washington lobbyist born in the former Soviet Union, who said he was attending at Veselnitskaya's request, and Irakly "Ike" Kaveladze, a 52-year-old executive from Huntington Beach, who is an executive in Agalarov's real estate company.
Mueller appears to be exploring the relationship between the Trumps and the Agalarovs, who were partners on a project for a Trump hotel in Moscow that was never built.
Kaveladze has been contacted by prosecutors in Mueller's office, said Scott Balber, Kaveladze's lawyer. Balber said his client was "cooperating fully" with investigators.
Manafort was Trump's campaign manager until last August. He resigned after investigators in Ukraine accused him of accepting $12.7 million in secret payments from Ukraine's ousted former president through an offshore shell company.
Manafort has denied receiving undeclared payments and has not been charged with any crimes. The FBI said in August it was investigating possible U.S. ties to corruption allegations against former Ukraine President Viktor Yanukovych, including Manafort's consulting work.
5:10 p.m.: Updated with new details including comments from President Trump and Sen. Jack Reed.