The House select committee investigating the Capitol attack on Monday issued new subpoenas to five political operatives associated with Donald Trump, including Roger Stone and the far-right media star Alex Jones, as the panel deepens its inquiry into the “Save America” rally that preceded the 6 January insurrection.

The subpoenas demanding documents and testimony expand the select committee’s inquiry focused on the planning and financing of the rally at the Ellipse, by targeting operatives who appear to have had contacts with the Trump White House.

House investigators issued subpoenas to the veteran operatives Stone and Jones, Trump’s spokesperson Taylor Budowich, and the pro-Trump activists Dustin Stockton and his wife, Jennifer Lawrence.

The chairman of the select committee, Bennie Thompson, said the subpoenas aimed to uncover “who organized, planned, paid for, and received funds related to those events, as well as what communications organizers had with officials in the White House and Congress”.

Thompson said in the subpoena letter to Stone that he was being subpoenaed to explain why he had been invited to lead the march to the Capitol on 6 January from the rally at the Ellipse, but curiously did not ultimately attend the rally or go near the Capitol.

The chairman also suggested that House investigators were interested in Stone’s connection to the Oath Keepers, the militia group he used as his private security detail before several members stormed the Capitol to stop the certification of Joe Biden’s election win.

Stone was also at a “command center” at the Willard hotel in Washington DC on 5 January, where Trump lieutenants strategized late into the night about how to subvert the results of the 2020 election at the joint session of Congress.

In the subpoena letter for Jones, the host of the far-right network InfoWars, Thompson raised the fact that he too did not lead the march from the rally from the Ellipse despite being invited to do so, in a potential indication he knew in advance about the Capitol attack.

The select committee also subpoenaed Budowich, a Trump spokesperson who sought to set up a social media and advertising campaign to promote attendance at the rally, according to the subpoena letter.

Thompson said, citing information on file with the select committee, that Budowich’s efforts extended to directing about $200,000 to rally organizers from unnamed donors “that was not disclosed to the organization to pay for the advertising campaign”.

The new detail about Budowich’s involvement in the financing of the rally could suggest that the select committee is aware of intimate connections between organizers and the Trump campaign, and that the level of coordination was deeper than previously known.

Congresswoman Zoe Lofgren, a member of the select committee, suggested on Saturday that the panel had uncovered new information pertaining to the Capitol attack, telling CNN they had interviewed more than 200 people.

The select committee also subpoenaed Stockton and Lawrence, pro-Trump activists who have ties to the ex-president’s former adviser Steve Bannon and allegedly helped organize the rally, according to their subpoena letters.

The new subpoenas came after counsel for the select committee said on Monday that allowing Donald Trump to block House investigators from accessing White House records held by the National Archives would threaten the safety of the 2022 and 2024 elections.

In court filings with the DC circuit of the US court of appeals, the select committee said the integrity of future elections would be in jeopardy if they were unable to learn everything they could about Trump’s efforts to overturn the results of the 2020 election.

“The select committee’s task to study and suggest legislation to ensure that January 6 is not repeated, and that our nation’s democracy is protected from future attacks, is urgent,” the House counsel Douglas Letter argued on behalf of the panel.

Trump sued last month to stop the select committee from receiving hundreds of pages of White House records from the National Archives, including memos by the former chief of staff Mark Meadows and former deputy White House counsel Pat Philbin, over executive privilege claims.