Sen. Ron Johnson, R-Wis., detailed a Secret Service briefing given to senators on Wednesday about the recent assassination attempt against former President Trump, saying there was "virtually no information" provided. "It's infuriating," he told Fox News Digital in an interview. "The director of the Secret Service did admit there were mistakes and gaffes," he added, referring to Kimberly Cheatle. But the briefing, which was given by a separate official, "was largely irrelevant," according to Johnson. Only four senators were allowed to ask questions and there were no follow-ups, he said. JD VANCE BY THE NUMBERS: FIRST SPEECH SIGNALS HEAVY CAMPAIGN PRESENCE IN BATTLEGROUND RUST BELT Sen. John Cornyn, R-Texas, questioned the agency on when they first became aware of the person who ultimately shot Trump and others at the outdoor rally in Butler, Pennsylvania, on Saturday, per Johnson. The briefer said they had been made aware of Thomas Crooks roughly an hour before he opened fire. "That is a $64,000 question. When did the sniper team identify [him]? When did they have him in [their] sights?" Johnson asked. "Did they request permission to alleviate the threat? Was it denied?" "Those are the questions. They're being asked," he said. Cornyn notably called for Cheatle's resignation following the call, writing on X, "The unexplained & inexcusable lapse in basic security measures requires a change in leadership at the Secret Service." FLASHBACK: A LOOK AT DONALD TRUMP'S REMARKS AT THE 2016, 2020 REPUBLICAN CONVENTIONS "They should have been providing that up front," Cornyn said. He suggested that it's counterintuitive for the service to withhold key information about the incident while stating that they want transparency and seek to prevent the spread of conspiracy theories. "They should be addressing what's out there right now," Johnson said. "They didn't." The Wisconsin Republican railed against the briefing by the service, saying, "They need to open it up so that people can ask detailed questions [and] follow-up questions." "That's not what this thing was," he said. "This was kind of a check-the-box, quick briefing. Not providing information, only gives four senators an opportunity to ask questions ... this is not providing the kind of information people need." He noted that the lack of information at the briefing led to different reporting from news organizations: "This is not the way it should be done." CHUCK SCHUMER PUSHED TO DELAY DNC AS CONCERNS PERSIST OVER BIDEN'S CANDIDACY The assassination attempt on Trump left him bloodied and with a wounded right ear but ultimately OK, enough so that he opted against pushing back his attendance at the Republican National Convention this week. One spectator was killed at the rally, Corey Comperatore. He was fatally shot while shielding his family from bullets. Two other people wounded at the event are hospitalized. Lawmakers have raised significant concerns after the shooting as more details suggest errors on the part of the Secret Service and law enforcement. Secret Service spokesman Anthony Guglielmi told Fox News Digital in a statement Thursday: "Continuity of operations is paramount during a critical incident and U.S. Secret Service Director Kimberly Cheatle has no intentions to step down." "She deeply respects members of Congress and is fiercely committed to transparency in leading the Secret Service through the internal investigation and strengthening the agency through lessons learned in these important internal and external reviews."