Hundreds of people filled the streets of downtown Burlington Thursday night to demand Congress protect special counsel Robert Mueller's probe into Russian meddling in the 2016 election.

Protesters brought traffic to a standstill as they marched from the Federal Building on Elmwood Avenue to City Hall, chanting "Let Bob do his job!" and "Two, four, six, eight! We want Mueller to investigate!"

Burlington Deputy Police Chief Jan Wright estimated the crowd to number between 300 and 400 people.

The protest, one of nearly a thousand scheduled to be held nationwide, was announced only 24 hours earlier. But organizers had been planning for about a year, ready to mobilize the day they feared President Donald Trump would begin moving to derail Mueller's investigation.

That day was Wednesday, when Trump forced Jeff Sessions to resign and placed oversight of the investigation in the hands of Matthew Whitaker, a former federal prosecutor who has publicly criticized the Mueller probe.

Prosecutors must be able to examine evidence and make independent decisions, Eugene Bergman, a recently retired Burlington assistant city attorney, told the crowd.

"The integrity of our system, the rule of law itself, depends on this freedom from political pressure," he said. "When the political boss exerts or tries to exert control of a prosecutor, it is an act of corruption."

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Former Gov. Madeline Kunin told the gathered crowd that giving Whitaker oversight of the investigation was manipulative and wrong.

She told the marchers to prepare for a long fight.

"We have to be vigilant," Kunin said. "We have to persist, and persist we will."

The protest was one of 11 across Vermont and nearly a thousand across the country. The rallies were part of a "Nobody is Above the Law Rapid Response," which has been organized by MoveOn.Org, according to the event's website.

Rachel Siegel, one of the organizers of the Burlington event, said she found it inspiring to see hundreds of thousands of people across the country marching at the same time.

She and the other organizers deliberately chose to wait to plan next steps to allow for feedback, and are holding a planning meeting Monday at noon at the Peace and Justice Center on Lake Street in Burlington.

"There's a plan to make a plan," she said.

Earlier: 'A threat to our Democracy'

The Vermont Democratic Party emailed supporters the list of protests, saying Trump fired Sessions in a clear attempt to end the Russia probe.

"This is a threat to our Democracy — to our very identity as Americans," the email read.

The Vermont congressional delegation quickly responded to the news of Sessions' firing by demanding that Mueller's independence be preserved.

Rep. Peter Welch, D-Vt, who will be part of the Democratic leadership that takes control of the House of Representatives in January, tweeted that the House must immediately pass legislation to protect Mueller.

Welch also said that Jeff Sessions was the worst attorney general in modern times.

Sen. Patrick Leahy, D-Vt, and Sen. Bernie Sanders, I-Vt., both called for Whitaker to recuse himself from overseeing Mueller because of his public comments about the investigation.

"President Trump has wanted to hobble the Russia investigation from its inception," Leahy said in a statement.

"The only reason why he regularly disparaged and belittled Attorney General Jeff Sessions, and ultimately asked for his resignation, is that he was unhappy that his Attorney General followed mandatory Department of Justice regulations and recused himself from the Russia investigation. And the President has now attempted to install a close ally of the White House in charge of this investigation."

Sanders also called on Congress to protect Mueller and said Trump must allow the investigation to continue unimpeded.

"Any attempt by the president or the Justice Department to interfere with Mueller’s probe would be obstruction of justice and an impeachable offense." he said.

Contact Jess Aloe at 802-660-1874 or jaloe@freepressmedia.com. Follow her on Twitter at @jess_aloe