WASHINGTON — The House committee investigating the Jan. 6 attack on the Capitol on Friday issued 14 subpoenas to people who were part of fake slates of electors for President Donald J. Trump in the 2020 election, digging deeper into his efforts to overturn the results.

The subpoenas target individuals who met and submitted false Electoral College certificates in seven states won by President Biden: Arizona, Georgia, Michigan, New Mexico, Nevada, Pennsylvania and Wisconsin.

“The select committee is seeking information about attempts in multiple states to overturn the results of the 2020 election, including the planning and coordination of efforts to send false slates of electors to the National Archives,” Representative Bennie Thompson, Democrat of Mississippi and the chairman of the committee, said in a statement. “We believe the individuals we have subpoenaed today have information about how these so-called alternate electors met and who was behind that scheme.”

The so-called alternate electors met on Dec. 14, 2020 in seven states that Mr. Trump lost and submitted bogus slates of Electoral-College votes for him, the committee said. They then sent the false Electoral College certificates to Congress, an action Mr. Trump’s allies and his campaign used to try to justify delaying or blocking the formal counting of electoral votes to confirm the election results during the Jan. 6, 2021 joint session of Congress.

The 14 individuals subpoenaed on Friday were: Nancy Cottle and Loraine B. Pellegrino of Arizona; David Shafer and Shawn Still of Georgia; Kathy Berden and Mayra Rodriguez of Michigan; Jewll Powdrell and Deborah W. Maestas of New Mexico; Michael J. McDonald and James DeGraffenreid of Nevada; Bill Bachenberg and Lisa Patton of Pennsylvania; and Andrew Hitt and Kelly Ruh of Wisconsin.

The subpoenas order the witnesses, all of whom claimed to be either a chair or secretary of the fake elector slates, to turn over documents and sit for depositions in February.

The committee’s subpoenas came as the Justice Department this week said it was investigating the fake electors.