WASHINGTON – It turns out Donald Trump wasn’t the only candidate the Russians allegedly tried to help during the 2016 presidential campaign.

A 37-page indictment resulting from special counsel Robert Mueller’s investigation shows that Russian nationals and businesses also worked to boost the campaigns of Vermont Sen. Bernie Sanders and Green party nominee Jill Stein in an effort to damage Democrat Hillary Clinton.

The Russians “engaged in operations primarily intended to communicate derogatory information about Hillary Clinton, to denigrate other candidates such as Ted Cruz and Marco Rubio, and to support Bernie Sanders and then-candidate Donald Trump,” according to the indictment, which was issued Friday.

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The document, which spells out in detail how the Russians worked to support Trump’s campaign, alleges that on or about Feb. 10, 2016, the Russians internally circulated an outline of themes for future content to be posted on social media accounts.

“Specialists were instructed to post content that focused on ‘politics in the USA’ and to ‘use any opportunity to criticize Hillary and the rest (except Sanders and Trump – we support them),’” the indictment said.

On or about Nov. 3, 2016, just five days before the election, the Russians tried to boost Stein’s campaign by buying an ad to post on the Instagram account “Blacktivisit,” according to the indictment. The ad read in part: “Choose peace and vote for Jill Stein. Trust me, it’s not a wasted vote.”

Sanders addressed the allegations made in the indictment in a pair of Twitter posts on Friday but did not talk about the charges that the Russians tried to help his campaign.

“It has been clear to everyone (except Donald Trump) that Russia was deeply involved in the 2016 election and intends to be involved in 2018,” Sanders wrote. “It is the American people who should be deciding the political future of our country, not Mr. Putin and the Russian oligarchs.”

“It is absolutely imperative that the Mueller investigation be allowed to go forward without obstruction from the Trump administration or Congress,” he said in another post.

Clinton has yet to comment publicly on the allegations made in the indictment. But she wrote in her book, What Happened, that she never imagined that Russian President Vladimir Putin would have “the audacity to launch a massive covert attack against our own democracy, right under our noses — and that he'd get away with it."

Clinton also wrote that Sanders’ attacks against her caused lasting damage by making it harder to unify progressives in the general election and paving the way for Trump’s “Crooked Hillary” campaign.

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Clinton’s campaign manager, Robby Mook, wrote in a series of Twitter posts on Friday that the Russian meddling amounted to an attack “by a foreign adversary.”

“Will our Congress and President stand strong and take action? Or let it happen again?” Mook wrote.

In another Twitter post, Mook said the indictment shows the Russian meddling went beyond cyberwarfare.

“Operatives were dispatched into our country to break our laws and attack our democracy,” Mook wrote.

“For someone who seems to enjoy playing the role of campaign operative in America, you’d think Putin would have the confidence to allow free and fair elections in Russia,” he said.

The indictment charges 13 Russian nationals and three businesses — including an Internet firm tied to the Kremlin — with conspiracy, identity theft, failing to register as foreign agents and violating laws that limit the use of foreign money in U.S. elections.

Prosecutors said officials at that firm, the Internet Research Agency, described their work as "information warfare against the United States" and their goal as "spreading distrust toward the candidates and the political system."