Story highlights Warren has been an attack dog of sorts for Clinton ever since she clinched the Democratic nomination

She also called Trump "a twisted bully who can't fight his own fights"

Washington (CNN) Massachusetts Sen. Elizabeth Warren tore into Republican presidential nominee Donald Trump on the campaign trail Saturday for lying about President Barack Obama's citizenship and hinting at violence against his Democratic opponent, Hillary Clinton.

Speaking to Clinton supporters at Ohio State University, Warren continued her ongoing feud with Trump by criticizing his admission Friday -- after five years of falsehoods -- that Obama was born in the US.

"Only when his handlers tied him down and forced him did he grudgingly admit that the man was born in the United States," Warren said. "What kind of a man does that? A man with a dark and ugly soul."

Later Friday, Trump, at a campaign event in Miami, cited Clinton's push for greater gun control to suggest the Democrat's Secret Service detail should disarm.

"Let's see what happens to her," Trump said. "Take their guns away, OK? It'll be very dangerous."

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