A top Senate Democrat blasted the Biden-Harris administration for "stonewalling" in response to requests for information on the assassination attempts on former President Trump and the potential failures of the U.S. Secret Service. 

Sen. Richard Blumenthal, D-Conn., chairman of the Permanent Subcommittee on Investigations (PSI) within the Homeland Security and Governmental Affairs Committee (HSGAC), said the Department of Homeland Security (DHS) was "almost derelict in its duty by resisting our requests for documents, evidence and information that are necessary to investigate."

The Democrat reiterated his disappointment in the department, and added that he has become "angry" that DHS has not been more "forthcoming." 

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split photo of Senator Richard blumenthal/Donald Trump/Senator Ron Johnson

Sen. Blumenthal, left, slammed DHS for stonewalling Congress' requests for information. (Michael Brochstein/SOPA Images/LightRocket/Kevin Dietsch/Andrew Harnik)

The Democrat foreshadowed potential subpoenas being used in the future, telling reporters on Monday, "We may need to require more cooperation from them. And we have the power to do so through the compulsory process. In other words, the subpoena power."

Sen. Ron Johnson, R-Wis., PSI ranking member, echoed Blumenthal's characterization of the DHS and its lack of transparency, claiming, "They're holding all their cards close to the vest."

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U.S. Senator Ron Johnson speaking during Senate committee hearing

Sen. Ron Johnson questions Secret Service Director Ronald Rowe Jr. and FBI Deputy Director Paul Abbate at a Senate Judiciary Committee hearing on the attempted assassination of former U.S. President Trump, on Capitol Hill, on July 30, 2024. (Umit Bektas/Reuters)

In fact, he said their withholding of information is "driving suspicion and driving conspiracy theories." 

As for his Democratic counterpart on the PSI and HSGAC, Chairman Gary Peters, D-Mich., Johnson said, "I hope they're getting frustrated."

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Speakers at the press conference with an update on the assassination attempt on former president Donald Trump

Acting Director Ronald Rowe Jr. of the U.S. Secret Service addresses the media at a press conference on the assassination attempt of former president Trump, West Palm Beach, Florida, Monday, Sept. 16, 2024. (Mega for Fox News Digital)

"I wrote a letter that it took us a couple weeks for all four offices to sign onto. That's the one that upset them because we sent it to Secret Service and DHS. We got a response in four hours, and the response was pretty disrespectful," he described. "And I think that fired up Chairman Peters and Chairman Blumenthal… I think that's the reaction you heard last week. They're not happy with the way they're treating them."

A DHS spokesperson responded, saying the agency "remains committed to working in good faith and making every effort to cooperate with the appropriate and relevant investigations into July 13th to identify how this happened and how to prevent it from happening again."

"Since July 13, the Department and the U.S. Secret Service have provided the Senate with multiple briefings, nearly 2,500 pages of documents, and more than 50 hours of transcribed interviews," the DHS said. "It has done so while also cooperating with investigations by the House Special Task Force, the Independent Review Panel directed by the President, the DHS OIG, and the Government Accountability Office. Claims that the Department and Secret Service are not cooperating are false and fail to recognize the robust response and ongoing work to meet Congress’ oversight requests, and our clear commitment to accountability for the events of July 13th." 

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Donald Trump plays golf at the Trump International Golf Club in West Palm Beach

Trump plays golf at the Trump International Golf Club in West Palm Beach, Florida, Dec. 30, 2020. (Reuters/Marco Bello)

The Secret Service did not immediately provide comment to Fox News Digital. 

On Sunday, the Secret Service opened fire at Trump International Golf Club in West Palm Beach, Florida, after seeing a suspect raising a weapon. The suspect fled the scene in a black Nissan SUV but was apprehended by authorities. 

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The suspect, 58-year-old Ryan Wesley Routh, had allegedly pushed the muzzle of an SKS rifle through the chain-link fence outside where Trump was golfing. 

The HSGAC and PSI had already been investigating the first assassination attempt in Butler, Pennsylvania, on July 13, most recently receiving a briefing from Acting Secret Service Director Ronald Rowe last week, which they said left them frustrated and disappointed by the uncovered failures.