10/09/2011 07:23 pm ET | Updated Dec 09, 2011

Darrell Issa: Eric Holder 'Fast And Furious' Claims 'Disingenuous'

WASHINGTON -- A key House investigator says he could send subpoenas to the Obama administration as soon as this week over weapons lost amid the Mexican drug war.

House oversight committee chairman Darrell Issa suggested on "Fox News Sunday" that Attorney General Eric Holder knew about the gun trafficking operation known as "Fast and Furious" earlier than he has acknowledged. Subpoenas could go out as soon as this week, Issa said.

“We want to know what did they know and when did they know it,” Issa said, who called Holder's claims of ignorance about the program "disingenuous on its face."

The Bureau of Alcohol, Tobacco, Firearms and Explosives in 2009 allowed intermediaries for drug cartels to buy thousands of weapons from Arizona gun shops and lost track of about 1,400 of the 2,000 of those guns. Some of those weapons have been recovered at crime scenes in Mexico.

Issa further attacked Holder, saying, "If we assume for a moment that he didn’t know, the question is: Is he competent?”

The GOP congressman has been outspoken about his disapproval of the Attorney General. Last month, Issa charged that Holder is so "inept that he is dangerous."

Watch the full interview on "Fox News Sunday" below: