The Pentagon on Tuesday sidestepped questions about whether top-secret intelligence, including secrets derived from reconnaissance satellites and aircraft, was compromised after being placed on unsecure emails found on Hillary Clinton’s private server.

Pentagon Press Secretary Peter Cook, in an inaugural briefing for reporters, would not answer questions about the secret intelligence found by an inspector general in a sampling of emails once stored on Clinton’s unsecured server. The email system was used by the former secretary of state from 2009 to 2013.

So far, some 305 emails containing classified data have been found among some 60,000 emails once kept on the private server.

"I think this an issue best left to the State Department," Cook said. "They’ve had to address this and also Secretary Clinton. It's not something that I think makes sense for me to get into from right here at this podium."

Cook also would not say if the Pentagon is conducting a damage assessment or investigating whether its secrets were compromised.

U.S. Intelligence Community Inspector General Charles McCullough disclosed in a notification to Congress Aug. 11 that samples of Clinton’s emails had revealed improperly stored intelligence information classified "Top Secret//SI//TK//Noforn" on the Clinton server.

Clinton initially denied placing any classified information on the email server, and later said she did not knowingly use data that was "marked" classified. Last week she stated, "I did not send classified material, and I did not receive any material that was marked or designated classified."

An email sent to the Clinton presidential campaign seeking comment was not returned.

The Pentagon and its associated intelligence agencies have been stung by two major security failures in recent years. The first involved the compromise of tens of thousands of classified documents stolen by Army Pvt. Bradley Manning and supplied to the anti-secrecy website Wikileaks. The second was the theft of an estimate 1.7 million classified NSA documents that were supplied to a number of news outlets, including the Washington Post.

SI is code for special intelligence and is used as a marker for documents that contain communications intelligence, usually produced by the National Security Agency. The TK designator stands for Talent Keyhole and is used as a marking on intelligence derived from reconnaissance systems. Both designators are among the highest security classification levels.

Storing such information on an unclassified email system is illegal under federal laws governing the handling of secret information.

The Pentagon, through the National Security Agency (NSA) and National Geospatial Intelligence Agency, or NGA, is the largest producer of classified information for the U.S. government. The NSA conducts cyber spying and electronic eavesdropping for intelligence labeled SI. The NGA controls and disseminates satellite intelligence in the TK category.

Talent is the code word for intelligence obtained from manned aircraft reconnaissance flights. Keyhole is used to label intelligence obtained from reconnaissance satellites.

Both code words are used to mark documents containing communications and photographic intelligence.

Despite the Wikileaks and Snowden disclosures, the Pentagon has made little effort to address what it calls the "insider threat" to its secrets.

Congress’ Government Accountability Office, in a report issued in June, said the Pentagon has not done enough to deal with the problem.

In the aftermath of the Wikileaks disclosures, Congress in 2011 directed the Pentagon to set up an insider threat program. The White House also produced a presidential memorandum creating a National Insider Threat Task Force that sought to designate senior officials who are in charge of addressing insider leaks.

"The recent disclosures of classified information by insiders have damaged national security, potentially placed the lives of military service members at risk, and highlighted the importance of preventing or mitigating future threats to DOD’s classified information and systems," the GAO said.

While some improvements have been made to DOD information security, "DOD components have not taken action to incorporate other key elements into their insider-threat programs because DOD has not issued guidance that identifies actions beyond the minimum standards that components should take to enhance their insider-threat programs."