About 40 subpoenas were issued by the Justice Department last week as part of its criminal investigation into the Jan. 6 attack on the U.S. Capitol, sources familiar with the matter tell ABC News.
Among those subpoenaed are close advisers to former President Donald Trump, as well as former White House officials and staffers from his 2020 presidential campaign ranging from lower-level staffers to those at the highest levels of the campaign.
At least one top Trump adviser, Boris Epshteyn, recently had his phone seized as part of this effort, the sources said.
Epshteyn did not respond to a request for comment from ABC News.
The New York Times first reported news of the roughly 40 subpoenas.
As ABC News has previous reported, the subpoenas are seeking information from witnesses about Trump's efforts to overturn the 2020 election, the events leading up to and surrounding the Jan. 6 attack, and the fundraising and spending efforts of the Trump-aligned Save America PAC.