Facebook is under fire after revealing that a Russian group tied to the Kremlin bought political ads on its platform during the 2016 elections.

Lawmakers are demanding answers, and liberal groups, who say the company failed to crack down on fake news, are seizing on the new disclosure.

Even Hillary Clinton Hillary Diane Rodham ClintonJeff Flake: Republicans 'should hold the same position' on SCOTUS vacancy as 2016 Momentum growing among Republicans for Supreme Court vote before Election Day Warning signs flash for Lindsey Graham in South Carolina MORE, the 2016 Democratic presidential nominee, has cited the ads when discussing her loss during a book tour.

"We now know that they were sowing discord during the election with phony groups on Facebook," Clinton told MSNBC's Rachel Maddow. "They were running anti-immigrant, anti-me, anti-Hillary Clinton demonstrations. They were putting out the fake news and negative stories untrue to really divide people."

ADVERTISEMENT

Sen. Mark Warner Mark Robert WarnerIntelligence chief says Congress will get some in-person election security briefings Overnight Defense: Trump hosts Israel, UAE, Bahrain for historic signing l Air Force reveals it secretly built and flew new fighter jet l Coronavirus creates delay in Pentagon research for alternative to 'forever chemicals' House approves bill to secure internet-connected federal devices against cyber threats MORE (Va.), the top Democrat on the Senate Intelligence Committee, has said the company needs to be more forthcoming about the full extent of the ad buys.

Sleeping Giants, an anonymous left-leaning activist group, is turning its sights on Facebook as well. The group gained attention by pressuring 2,600 advertisers to remove their ads from conservative website Breitbart and is now pressing Facebook to be more transparent about how Kremlin-linked groups used the platform.

Beyond revealing that Kremlin-linked Internet Research Group spent $100,000 buying ads on the social media platform in 2016, Facebook has said little else publicly.

The company is sharing more privately with federal investigators. But lawmakers on intelligence committees in the House and Senate are complaining that Facebook still isn’t providing enough details.

“We need to get a lot more from the technology companies,” Rep. Adam Schiff Adam Bennett SchiffTop Democrats call for DOJ watchdog to probe Barr over possible 2020 election influence Overnight Defense: Top admiral says 'no condition' where US should conduct nuclear test 'at this time' | Intelligence chief says Congress will get some in-person election security briefings Overnight Defense: House to vote on military justice bill spurred by Vanessa Guillén death | Biden courts veterans after Trump's military controversies MORE (Calif.), the top Democrat on the House Intelligence Committee, said Friday on “Morning Joe.”

Schiff suggested Facebook has been slow to release details because “it’s against their economic interest to be advertising problems about how a foreign government was exploiting their technologies.”

Warner admitted on Wednesday that Facebook had not shared that the Russian group involved had purchased ads for anti-immigration and anti-Muslim rallies that they organized on Facebook.

The senator only became aware of those ads after a Daily Beast report.

According to the report, the Russian group tried to rally Americans to show up at political events in Iowa and other states. Subsequent reports showed that the Russian group created a Texas fan page, which disseminated pro-Texas secessionist messages. Facebook ultimately took the page down.

“I question whether Facebook has put near the resources they need into getting us all the facts,” Warner told reporters on Wednesday.

The Virginia Democrat said he thinks Facebook itself doesn’t know the extent to which Russian groups used its platform to interfere in the presidential election.

“They had a fairly narrow search,” Warner said last Friday. “They’ve not looked at things like Moldova,” he told reporters the following Thursday. “They’ve not looked at other countries where there’s lots of indication of trolls being used.”

Facebook says its hands are now tied, but it could provide more information publicly in the future.

“Due to federal law and ongoing investigations, we’re limited in what we can share publicly,” a Facebook spokesperson said when speaking with The Hill.

The company is still providing briefings to lawmakers on the matter.

Warner said he would like to see changes to the law so that Facebook advertisers would be required to disclose who is funding political ads.

Facebook says it’s open to considering such legislative solutions.

The attention isn’t only coming from Democrats.

Senate Intelligence Committee Chairman Richard Burr Richard Mauze BurrRep. Mark Walker says he's been contacted about Liberty University vacancy Overnight Defense: Trump rejects major cut to military health care | Senate report says Trump campaign's Russia contacts posed 'grave' threat Senate report describes closer ties between 2016 Trump campaign, Russia MORE (R-N.C.) has said he likely wants a hearing on the political ad buys.

The scrutiny on Facebook has spread to other social media giants.

Twitter and Google have remained silent on the subject of Russian influence on their platforms. Twitter says it will provide analysis of Russian activity to investigators. Warner said this week that Twitter is scheduled to brief the Senate Intelligence Committee, but he did not specify when.

Google says it has not seen evidence of Russian advertising on its platform.

But groups are hammering Facebook over the matter and calling for changes.

"It’s clear that they’re not doing enough across the board," a Sleeping Giants spokesman told The Hill. "There's not enough transparency in anything they’re doing.

"When you’re dealing with campaign funds and who’s placing ads, it seems that should be getting the same scrutiny as TV ads," the spokesman added.

It is still unclear how Facebook will respond and if the company will make any changes to its practices.

Representatives from the company did not share any plans to do so with The Hill.

Even lawmakers who have been critical of Facebook acknowledged that addressing the problem was complicated but said social media companies need to be more aware.

"What makes this so difficult frankly is that it’s as though we cannot simply ask them to send us our data and analyze it ourselves," Schiff said.

"We need their own willingness to devote considerable resources to looking at what happened on their own systems and we need to be able to rely on the information that they provide us."