Edward Snowden downloaded 1.7 million intelligence files from US agencies, the most secrets ever to be stolen from the US government in a single instance in the nation’s history, according to lawmakers who have viewed a classified Pentagon report.

Legislators who saw the secret report claimed that many of the documents taken by Snowden regarding military options could put personnel at risk, although they did not delve into specifics.

“This report confirms my greatest fears – Snowden’s real acts of betrayal place America’s military men and women at greater risk. Snowden’s actions are likely to have lethal consequences for our troops in the field,” Rep. Mike Rogers (R-Mich.), chairman of the House Intelligence Committee said in a statement. Rogers had recently ignited some controversy after joking that Snowden should be placed on a military “kill list.”

The whistleblower downloaded all of the material he would eventually leak while earning over $100,000 annually and working at an NSA facility in Hawaii last year. The Washington Post reported that if Snowden did indeed download 1.7 million he may have only released small percentages of that total to individual journalists.

Rep. Dutch Ruppersberger (D-Md.) – the ranking member of the House Intelligence Committee – agreed with Rogers, claiming the amount of information Snowden took could “gravely impact” US national security. Yet others, including American Civil Liberties attorney and Snowden adviser Ben Wizden, say government officials are overstating the risk.

“This is straight from the government’s playbook,” Wizner said. “Remember, the government told the Supreme Court that publication of the Pentagon Papers would cause grave danger to national security. That was not true then, and this report is not true now. Overblown claims of national security rarely stand the test of time.”

Sources came forward in August, two months after the press began reporting Snowden’s leaks, to admit that authorities were unsure exactly how many documents Snowden obtained.

Two anonymous officials told NBC News at the time that the NSA was using poor compartmentalization techniques - meaning that Snowden, an IT systems administrator, was able to freely comb through agency networks containing a wide range of data. NSA Director Keith Alexander said in August that the government knew what Snowden had taken, while the NBC sources in fact said the NSA was “overwhelmed” with trying to find out the details.

Alexander said in an October speech that the documents were “being put out in a way that does the maximum damage to NSA and our nation.” He also told the audience that Snowden had far fewer documents to reporters than this week’s Pentagon report described.

“I wish there was a way to prevent it,” he told a Baltimore, Maryland crowd. “Snowden has shared somewhere between 50,000 and 200,000 documents with reporters. These will continue to come out.”