UPDATED 2:51 p.m. ET
(CBS News) Republican lawmakers on Tuesday stepped up their attacks of Attorney General Eric Holder, with one senator calling for the controversial cabinet member to step down.
Texas Republican Sen. John Cornyn called on Holder to step down at a hearing of the Senate Judiciary Committee. Holder was there to answer questions about the Obama administration's response to a report in the New York Times about U.S. efforts to curtail Iran's nuclear program.
The New York Times reported earlier this month that the United States is using computer warfare to attack Iran's nuclear program.
"You leave me no alternative but to join those that call upon you to resign your office. Americans deserve an attorney general who will be honest with them," Cornyn told Holder, citing the intelligence leaks to the New York Times and other issues including the scandal surrounding the department's controversial "Fast and Furious" program that allowed thousands of guns to get into the hands of Mexican drug cartels. Cornyn was one of only two senators on the panel who voted against Holder's initial confirmation to the post in 2009.
"With all due respect, senator, there is so much that is factually wrong with the premises that you started your statement with, it's almost breathtaking in its inaccuracies," Holder said.
The attorney general has called on a pair of U.S. attorneys to look into the intelligence leaks.
Iowa Republican Sen. Charles Grassley criticized the decision to have U.S. attorneys, who are politically appointed, to look into the matter and said Holder should instead appoint an independent special prosecutor to head the probe to avoid any appearance of conflict of interest.
Holder called the two U.S. attorneys, Ron Machen and Rod Rosenstein, experienced and highly respected.
"They are good lawyers, they are tough prosecutors," Holder said.
Arizonacalling for the appointment of a special counsel to investigate the leaks.
"I can't think of any time that I have seen such breaches of ongoing national security programs as has been the case here," McCain said.
South Carolina Republican Sen. Lindsey Graham said Holder did not understand the magnitude of the situation.
"I think you are missing the fact that this is a very big deal. And you are handling it in a way that creates suspicions where there should not be," Graham said as Alabama Republican Sen. Jeff Sessions said "these leaks could very well be criminal."
Separately, New York Republican Rep. Peter King, who chairs the House Committee on Homeland Security, said the leak is worse than Watergate scandal that brought down President Richard Nixon.
"It is far more important," King said in an interview with Fox News Radio, "to me, there is no comparison at all."