Protesters shout candidates off stage: 'Black lives matter!'

Black Lives Matter and Black Immigration Network activists shout down the first of two Democratic presidential candidates speakers at a Netroots Nation town hall meeting on July 18, 2015, in Phoenix, Ariz. (Photo by Ross D. Franklin/AP)
Black Lives Matter and Black Immigration Network activists shout down the first of two Democratic presidential candidates speakers at a Netroots Nation town hall meeting on July 18, 2015, in Phoenix, Ariz.

This article has been updated.

PHOENIX – Protesters shouted two presidential candidates off stage on Saturday at Netroots Nation, demanding policy proposals on racial tensions and police brutality.

Both candidates -- former Maryland Gov. Martin O'Malley and Vermont Sen. Bernie Sanders -- struggled to appease the angry protesters while sticking to their talking points and both ultimately failed to capitalize on the unexpected interruption, which comes amid a national conversation on racial tensions and police brutality. Just last week, a black woman named Sandra Bland died in police custody after being arrested for a traffic violation in Texas. Meanwhile, Friday marked the first anniversary of Eric Garner’s chokehold death at the hands of NYPD officers in Staten Island.

Alternating chants of "black lives matter" and "say her name," protesters forcefully approached the stage part of the way through O’Malley’s conversation with journalist Jose Antonio Vargas.

“It's not like we like shutting s**t down, but we have to," Black Lives Matter founder Patriss Cullors said. "We are tired of being interrupted."

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“Every single day folks are dying. Not being able to take another breath. We are in a state of emergency,” Cullors continued, hoarse from chanting. “If you don't feel that emergency, you are not human.”

After much chanting – and pleas from event organizers to give O’Malley a chance to respond to their questions – the former Maryland governor began to speak about criminal justice reform, promising a detailed policy proposal soon and saying he supported forcing police districts to report brutality complaints. Protesters interrupted him, chanting, “black lives matter.”

“I know, I know ... Let me talk a little bit ... Black lives matter, white lives matter, all lives matter,” O’Malley answered earning boos and shouts from the protesters and gasps from the rest of the audience.

He left the stage shortly thereafter.

Sanders – who was widely expected to be the favorite candidate this weekend -- took the stage to chants from protesters, who made it clear they wanted answers from him as well.

"Black lives of course matter but I have spent 50 years of my life fighting for civil rights and if you don't want me to be here, that's OK,” Sanders said with visible exasperation. "I will answer your question, but I'd like to speak for a couple of minutes, I was told ..."

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Sanders tried to turn the conversation back to his talking points – focusing on economic inequality and highlighting African-American unemployment and the racial disparities in the justice system – but struggled to shout over protesters who refused to relent.

Sanders left the stage, abbreviating his appearance significantly. 

Despite interruptions, the event ended 15 minutes earlier than scheduled. Vargas later tweeted later that he would have liked to continue the conversation, but that he wouldn't silence the protesters voices to do so.

Netroots Nation released a statement an hour after the event ended, saying the group "stands in solidarity with all people seeking human rights."

"Although we wish the candidates had more time to respond to the issues, what happened today is reflective of an urgent moment America is facing today," the group said in a statement, highlighting next year's conference location -- St. Louis -- which aims to put a direct focus on race issues in the wake of Michael Brown's shooting death at the hands of police nearby in Ferguson, Missouri.

Attendees, however, noticed that organizers apologized to O’Malley via a teleprompter. 

"We were apologizing for the interruption but believe the message Gov. O'Malley and Sen. Sanders heard today is urgent and necessary," a spokesman told msnbc.