Sen. John CornynJohn CornynSenate approves .3 trillion spending bill, sending to Trump GOP senator threatened to hold up bill over provision to honor late political rival: report Overnight Health Care: House passes .3T omnibus | Bill boosts funds for NIH, opioid treatment | Senators spar over ObamaCare fix | 'Right to Try' bill heads to the Senate MORE (R-Texas) said Wednesday that Attorney General Eric HolderEric Himpton HolderWisconsin GOP will tinker with election laws rather than follow court order Judge orders Walker to hold special elections Holder: 2018 vote crucial to combating gerrymandering MORE failed to "acquit himself" in his testimony Tuesday over the controversial 2009 gun-tracking operation Fast and Furious.

"He's held no one accountable," Cornyn told "Fox and Friends."

Tuesday's Senate Judiciary Committee hearing was the first congressional hearing since memos revealed Holder's office knew early on about the botched ATF operation. Republicans have called for Holder's resignation since the memos were uncovered, and Cornyn, among others, grilled the attorney general.

Cornyn asked Holder whether he has apologized to the family of Border Patrol agent Brian Terry, whose death has been linked to one of the guns sold by Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) agents to suspected purchasers for Mexican drug cartels. The ATF operation intended to track guns sold to suspected criminals, but the agency lost track of the guns. Two of the guns were found at Terry's murder scene last December.

“I have not apologized to them, but I certainly regret what happened,” Holder said at the hearing.

However, he also pushed back against faulting the operation for Terry's death.

“It pains me whenever there is the death of a law enforcement official, especially under the circumstances,” Holder said. "It is not fair, however, to assume that the mistakes that happened in Fast and Furious directly led to the death of Agent Terry." 

Cornyn kept pushing Holder on Terry at the hearing. "I was trying to give him an opportunity to do the right thing," he said on FOX. "He declined."

Cornyn said he still has a lot of questions about the operation, saying he is not sure yet whether Holder is "intentionally" misleading Congress or is simply ignorant of what takes place within the agency. 

"I'm not sure which is worse," he added. "[Holder is] not a stupid man, he's an intelligent man, and he should know better."

Holder told the committee that the the controversial gun-tracking operation was "flawed" in concept and execution. "This should never have happened. And it must never happen again," the atorney general said.