Republican senators accused big tech of 'interfering' in the elections.
Judiciary panel plans to vote to subpoena CEO Jack Dorsey to appear Oct. 23.
Platforms blocked users from sharing NY Post story with information purported to be from Hunter Biden's lap top.
Sites initially said it violated policies on hacked material and personal info.
Sen. Ted Cruz said both he and the Post were blocked from sharing the story.
Senate Republicans announced Thursday they plan to haul in Twitter exec Jack Dorsey for testimony about social media companies blocking users from sharing explosive reports about Hunter Biden that emerged this week.
They plan to subpoena Dorsey to appear before the Judiciary Committee days before Election Day.
'We have seen big tech, we've seen Twitter and Facebook actively interfering in this election in a way that has no precedent in the history of our country,' fumed Texas Sen. Ted Cruz Thursday, as the panel met for its fourth day of hearings on Supreme Court nominee Amy Coney Barrett.
'This is election interference and we're 19 days out from an election,' Cruz said after the social network blocked links to the article by the New York Post alleging corruption by Biden in Ukraine.
He said he himself was blocked from sharing another story about Hunter Biden Thursday.
Cruz, Judiciary Committee Chairman Lindsey Graham, and Sen. Josh Hawley of Missouri said the the panel will vote Oct. 20 on issuing the subpoena, with a plan to haul Dorsey before its members Friday Oct. 23, just days before Election Day.
Cruz said the Senate Judiciary Committee would vote next Tuesday to subpoena Dorsey to testify at the end of next week and 'explain why Twitter is abusing their corporate power to silence the press.'
'The Senate Judiciary Committee wants to know what the hell is going on,' he said.
'Twitter and Facebook and big tech millionaires don't get to censor political speech and actively interfere in the election. That's what they are doing right now.'
Republican Senator Josh Hawley announced separately that he had sent letters to Dorsey and Facebook chief executive Mark Zuckerberg asking them to appear before his Judiciary Subcommittee on Crime and Terrorism.
The hearing will 'consider potential campaign law violations' in support of Biden with the blocking of the article.
Dorsey apologized Thursday for the company's speedy action, which he said lacked adequate explanation.
Twitter initially said the story violated policies on 'hacked materials' and on 'personal and private information.'
'Our communication around our actions on the NYPost article was not great. And blocking URL sharing via tweet or DM with zero context as to why we're blocking: unacceptable,' Dorsey said.
He then linked to a statement from the company that said it was restricting the link because 'personal and private information' had been shared in the story.
President Donald Trump called it 'so terrible' that they 'took down' the story, and threatened to repeal 'Section 230' of a communications law, which protects companies from being held liable for information posted by third parties on their sites.
The story was based on information the Post said was provided by Donald Trump lawyer Rudy Giuliani. A computer repair store owner said a man he couldn't identify brought three computers into his shop for repair last fall, and that he then made a copy and provided it to the FBI and to Giuliani's lawyer.
The post has published business emails as well as photos of Biden, and says it contains explicit information as well.
The Post's story purported to expose corrupt dealings by Biden and his son Hunter Biden in Ukraine.
The newspaper claimed that the former vice president, who was in charge of US policy toward Ukraine, took actions to help his son, who in 2014-2017 sat on the board of controversial Ukraine energy company Burisma.
But the newspaper's source for the information raised questions.
It cited records on a drive allegedly copied from a computer said to have been abandoned by Hunter Biden, that Trump lawyer Rudy Giuliani gave to the Post.
The report also made claims about Joe Biden's actions in Ukraine which were contrary to the record.
Wary of 'fake news' campaigns, both Facebook and Twitter said they took action out of caution over the article and its sourcing.
'This is part of our standard process to reduce the spread of misinformation,' said Facebook spokesman Andy Stone.
The role of Giuliani, who has repeatedly advanced unproven and poorly sourced conspiracy theories about the Bidens and Ukraine, also raised flags.
The Biden campaign rejected the assertions of corruption in the report, but has not denied the veracity of the underlying materials, mostly emails between Hunter Biden and business partners.
Trump, who trails Biden in polls 19 days before the presidential election, blasted the two social media giants on Wednesday.
'So terrible that Facebook and Twitter took down the story of 'Smoking Gun' emails related to Sleepy Joe Biden and his son, Hunter, in the @NYPost,' Trump posted on Twitter.
Graham complained by pointing to information that was available in 2016 without being blocked. 'The Steele dossier was all over the place, they never blocked that, all the allegations about Russian collusion and Trump and every other idea that Trump may have done something bad, nobody blocked that,' he said.