Three protests were planned for Saturday during day two of the National Rifle Association Convention at the Kay Bailey Hutchinson Convention Center.
Dallas police tweeted early Saturday morning that several streets downtown were closed, and additional roads may also close throughout the day.
The first protest, a student-led "RALLY4REFORM," started at City Hall at 10 a.m. Organizers said they're protesting "NRA leadership's dangerous agenda."
Organizers of Rally4Reform said they are advocating against gun violence not just in schools.
"It's happening in public outdoor spaces, it’s happening in concerts, in everyday urban neighborhoods," said Azhalia Leal, who helped organize the protest.
Parents, teachers, and other groups joined the students for the rally.
Parkland shooting victim Joaquin Oliver's father, Manuel Oliver, was also at the rally.
Oliver painted a mural during the rally featuring President Trump and NRA spokeswoman Dana Loesch.
About 100 people attended the second protest, a gun-rights rally organized by North Texas Patriots for Liberty, which began at City Hall at noon. The group said they're rallying to "protect our 2nd Amendment rights in the State of Texas."
The third rally was organized by the #NoRA Initiative, a group co-founded by actress Alyssa Milano. That rally started at noon at Belo Garden Park.
Rally organizers said their objective is to "fight for gun control and combat the NRA's toxic influence over our political system."
Fred Guttenberg, the father of a Stoneman Douglas shooting victim, spoke to the crowd urging them to vote out lawmakers who refuse to pass "common sense gun reform."
He said he’d like to see the age requirement for buying all guns upped to 21, a three day waiting period, universal background checks and a ban for high capacity magazines and bump stocks. He’d also like to see red flag laws that allow law enforcement to block certain individuals, like those charged with domestic abuse, from buying guns.
"This will be a defining issue in this next election. And those of you on the wrong side of this at your next election, unless you’re choosing to retire as some are, you will be fired," Guttenberg said.
While there were no immediate reports of violence or arrests, an NBC 5 reporter observed a minor confrontation at the Belo Garden Park rally, which resulted in an NRA supporter being escorted out of the park.
Police said street closures include Young Street between Ervay Street and Griffin Street. South Akard Street between Canton Street and Young Street will also be closed.
The closures are expected to last from 7 a.m. to 10 p.m.
Sunday is the final day of the NRA Convention. About 80,000 people were expected to attend the event, along with 800 vendors.
On Friday, President Donald Trump spoke at the convention, along with Vice President Mike Pence and Gov. Greg Abbott.
NBC 5's Meredith Yeomans, Allie Spillards and Lexie Houghtaling contributed to this report.