TEXAS (CBSDFW.COM/CNN) — Several Texas events supporting Democratic presidential nominee Joe Biden were canceled because of security concerns.

The threats and alleged criminal activity centers around a group of President Trump supporters who reportedly followed the Biden-Harris campaign bus as it made stops across the state.

The Biden-Harris bus made a brief appearance in downtown Austin on Friday. Texas Democrats were scheduled to host speakers including Austin Mayor Steve Adler,  Rep. Lloyd Doggett (D-Tex.) and U.S. House candidate and former Texas state lawmaker Wendy Davis, but the group told CBS Austin they canceled the event so as to not to take attention from Democratic vice presidential nominee Kamala Harris — who made a stop in Fort Worth and two other Texas cities on Friday.

Pictures and videos posted on social media showed a long line of vehicles with pro-Trump signage trailing, and at times surrounding, the Biden-Harris bus as it traveled from San Antonio to Austin.

Rep. Rafael Anchía, a Dallas Democrat who chairs the Mexican American Legislative Caucus, tweeted that the Trump supporters were “armed” and “ramming volunteer vehicles & blocking traffic for 40 mins.”

Earlier in the week in Missouri City, Texas — a Houston suburb — Trump supporters showed up driving a hearse that had a sign on it that read, “vote like your life depends on it.” That same vehicle is believed to have been a part of Friday’s convoy.

Referencing the number of American deaths from COVID-19, Anchía commented about signs on the Trump supporter vehicle, “At least the Trump hearse is appropriate given the 200K+ Americans who have died due to his incompetence.”

A representative with the Travis County Democrats said it’s the same dozen or so people looking to disrupt events and they’ve been doing it all across the country.

Representative Sheryl Cole (D-Austin) tweeted the Biden-Harris bus was supposed to make a stop in Pflugerville, Texas with the Austin Young Democrats but she wrote they, too, had to cancel due to security reasons. Pro-Trump protesters have “escalated well beyond safe limits,” she said.

Hrair Balian, director of the Conflict Resolution Program at The Carter Center, said, “Both leaders have to call for calm.” He says between prior violent protests and the potential for not knowing results on Election Day could mean Texas and the nation is slated to see more confrontations like what was seen Friday.

“Dehumanizing the other side and seeking to take everything themselves and leave nothing for the other side… those are signals that things may go very wrong,” Balian said.

Travis County Democratic Party chair Katie Naranjo tweeted that Trump supporters followed the bus in an attempt to intimidate Biden voters. “They ran into a person’s car, yelling curse words and threats. Don’t let bullies win, vote.”

Early voting in Texas ended on October 30. Election Day is Tuesday, November 3.