Speaker Nancy Pelosi on Wednesday strongly rebuked Facebook, saying the company’s refusal to take down altered videos of her demonstrated how the social network contributed to misinformation and enabled Russian interference in the 2016 presidential election.

“We have said all along, poor Facebook, they were unwittingly exploited by the Russians,” Ms. Pelosi said in an interview with the public radio station KQED. “I think wittingly, because right now they are putting up something that they know is false.”