With few details still known about Thomas Matthew Crooks, the would-be assassin of former President Trump, one member of the House task force probing the assassination attempt is saying the FBI has not been forthcoming with their investigation.

Rep. Mike Waltz, R-Fla., a member of the Bipartisan Assassination Task Force, appeared on "Fox News Sunday" with fellow task force member Rep. Madeleine Dean, D-Penn., to discuss the group's investigation into the U.S. Secret Service’s (USSS) failures during the July rally in Butler, Pennsylvania, where Crooks fired a series of bullets from a rooftop that was left unchecked.

While Waltz and Dean both said the failures appear to rest with USSS, which has since taken full responsibility, Waltz appreciated that the agency has been forthcoming with the investigation, whereas the FBI – over two months after the assassination attempt – has not.

"The Secret Service is being forthcoming about its failures in communication guidance to locals having appropriate command posts. The FBI, on the other hand, is completely stonewalling this task force," Waltz said. "It has not been forthcoming."

TRUMP ASSASSINATION ATTEMPT IN FLORIDA: SECRET SERVICE ‘REDLINES,’ PENNSYLVANIA TASK FORCE SAYS

Trump is seen with blood on his face as Secret Service agents surround him and rush him off the stage at a rally in Butler, Pennsylvania, on July 13. (Rebecca Droke/AFP via Getty Images)

In July, FBI Director Christopher Wray initially told House lawmakers that "there’s some question about whether or not it’s a bullet or shrapnel that, you know, hit his ear." Two days later, the bureau issued a statement saying: "What struck former President Trump in the ear was a bullet, whether whole or fragmented into smaller pieces, fired from the deceased subject’s rifle."

Waltz said he’d like to see Wray and Department of Homeland Security Secretary Alejandro Mayorkas hold a press conference like the one USSS recently held.

"We still know virtually nothing about Crooks, the shooter in Butler, about his encrypted accounts, how he learned to build those IEDs," the congressman said.

On Thursday, Sen. Ron Johnson, R-Wisc., ranking member of the HSGAC Permanent Subcommittee on Investigations, said that what few documents the FBI provided lawmakers were "heavily redacted."

"I've never seen this," Johnson told reporters of the redactions.

The July 13 Trump rally shooting has heightened scrutiny of USSS, and prompted conversations about whether elected officials are being sufficiently kept safe in today’s hyper-partisan environment.

Acting Director Ronald Rowe Jr. of the U.S. Secret Service addresses the media at a press conference with updates on the investigation into the second apparent assassination attempt of former President Donald Trump in West Palm Beach, Florida, on Sept. 16. (Mega for Fox News Digital)

Waltz said another point of "mounting bipartisan frustration" with the FBI involved Iran, specifically the regime’s multiple ongoing plots to kill Trump and its hacking of Trump campaign information, which it then shared with the Biden-Harris campaign.

TRUMP HAS ‘PRESIDENTIAL LEVEL’ SECRET SERVICE PROTECTION, LAWMAKERS TOLD

"And when asked about it behind closed doors, the FBI would not give us any information to the Intelligence Committee," Waltz said. "Just this week. It's completely unacceptable and we need to issue those subpoenas."

Dean added that it "makes sense" for the task force to investigate the second apparent assassination attempt against Trump that occurred at Trump International Golf Club in West Palm Beach, Florida, on Monday, and condemned all political violence.

CLICK HERE TO GET THE FOX NEWS APP

"I want to set a baseline, which is that political violence has no place in this country," the congresswoman said.