Left-wing protesters interrupted 2020 presidential front-runner Joe Biden while he was speaking at the presidential debate Thursday night.

A protester is removed during the Democratic presidential primary debate. (AP Photo/David J. Phillip)

At the end of the debate, the moderators asked each candidate to explain a professional setback they experienced and how they were able to overcome it. The first candidate to be offered the opportunity to answer this question was the former vice president.

As Biden began to speak about how he dealt with his family tragedies, protesters interrupted him, chanting: "Three million deportations." One of the protesters wore a shirt that said "No human being is illegal on stolen land” on the back. "Defend DACA," another shirt read. DACA stands for Deferred Action for Childhood Arrivals, the policy that allows some illegal immigrants brought to the United States as children to receive a renewable two-year period of deferred action from deportation.

Some demonstrators chanted, "We are DACA recipients. Our lives are at risk."

Here are the protesters who were removed just before Biden's final statement at the #DemDebate



Two of their shirts read "DEFEND DACA, ABOLISH ICE, CITIZENSHIP FOR ALL" pic.twitter.com/chP1UHNomA — Bloomberg TicToc (@tictoc) September 13, 2019

I think protesters were saying “3 million deportations” while Joe Biden was asked about his biggest setback. #DemDebate https://t.co/iWMIErvoxJ — Zachary Siegel (@ZachWritesStuff) September 13, 2019

During July's presidential debate, there were multiple instances of protesters interrupting candidates, and this wasn't the first time Biden was the target. At that debate, hecklers broke out into chants of "3 million deportations," which is a reference to the number of deportations that occurred under the Obama administration.

In another instance, New York City Mayor Bill de Blasio, who did not qualify for Thursday's debate, was heckled by protesters over the death of Eric Garner at the hands of New York police officer Daniel Pantaleo.