U.S. President Donald Trump on Tuesday again criticised social media companies Facebook Inc, Alphabet Inc’s Google and Twitter Inc, alleging that they were biased against him and other Republicans, but offering no evidence.

Trump accused the companies of blocking his followers and making it harder for people to follow him. The companies have said in recent months that they have removed suspicious accounts after the networks were used in misinformation campaigns attempting to influence voters in the 2016 U.S. presidential race and other elections.

An analysis for the Senate Intelligence Committee released Monday described an organized campaign by the St Petersburg-based Internet Research Agency (IRA) to hurt Hillary Clinton, the Democratic nominee, by inflaming right-wing conspiracy theories and suppressing the vote of traditionally liberal groups such as African Americans.

The IRA-created account “Blacktivist” sent out messages such as: “No lives matter to Hillary Clinton. Only votes matter to Hillary Clinton.”Separately, a portion of the 3,841 IRA accounts on Facebook, Instagram, Twitter and YouTube studied by the researchers sought to provoke Republican-leaning white Americans to get out and vote.

And after Trump took office Moscow’s operatives took aim at Special Counsel Robert Mueller, head of the investigation into Russian interference in the 2016 presidential election and possible collusion between Trump’s campaign and Moscow, The Washington Post reported Monday.

Trump is a regular critic of social media and accused Twitter as recently as October of stifling the growth of his account by making it harder for users to follow him.

Marketing software firm SparkToro revealed in October that its analysis of his 55 million-plus followers had revealed that more than 60 percent were fake.

Around three-quarters of accounts that followed Trump had been in action for at least 120 days while 36 percent used Twitter’s default profile image.