(NBC News) Questions are mounting about whether the Central Intelligence Agency can be trusted as leading Senators accuse the agency of interfering with a Congressional investigation into a controversial interrogation program.
In an uncharacteristic display of frustration Senator Dianne Feinstein lashed out at the CIA Tuesday, accusing the agency of searching Congressional committee computers used in an investigation into CIA interrogation tactics during the Bush administration.
"I have grave concerns that the CIA's search may well have violated the separation of powers and principles embodied in the Constitution," Feinstein said.
CIA Director John Brennan is denying the allegations, calling them "beyond the scope of reason."
The escalating battle centers around a long investigation into harsh interrogation tactics like water-boarding, a practice ended by President Obama.
Senator John McCain is suggesting an independent investigation may also be needed to determine whether the CIA overstepped its authority.
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