» Protests are held in other Texas cities.

AUSTIN — State and local police had to keep crowds of protesters from blocking traffic along Interstate 35 across from the Police Department building here Saturday. The protesters also gathered on the south steps of the Capitol.

Demonstrators shouted, “Hands up don’t shoot,” as Austin police officers used pepper spray and rubber bullets to disperse crowds blocking the interstate’s frontage roads.

At least one downtown business, a Starbucks on Congress Avenue, was vandalized with spray paint as protesters walked through downtown.

Police Chief Brian Manley warned on Twitter that authorities would crack down on unlawful behavior.

“We appreciate peaceful protest and will continue providing a safe space for the community to express emotions,” Manley tweeted. “That being said, violence and destruction of property will not be tolerated.”

While waves of protesters moved away from the police headquarters toward the

Capitol and elsewhere downtown, dozens remained at the police building, where state police in riot gear and Austin police officers formed barricades around it.

The officers stood face to face with people who sometimes shouted obscenities at them.

“I feel like I have to be here for my children,” said Austin resident Katrina Hill. “I’m a mother and I have sons. It’s exhausting being black and being in America, because you always have to be on guard. It’s horrible. It’s scary.”

At one point, a man on a motorcycle tried to drive through a crowd of protesters on the northbound frontage road. The motorcyclist was ripped from his vehicle and beaten. Police quickly intervened and let the man drive away while forming a barricade that pushed protesters off the road.

Gov. Greg Abbott announced Saturday that he is making state resources available to cities to help control local protests.

Abbott offered troopers to help municipal police in Austin, San Antonio, Dallas and Houston, where nearly 200 people were arrested after Friday-to-Saturday overnight demonstrations. Abbott said the Texas Department of Public Safety has sent more than 1,500 officers to assist local police departments.

“Texas and America mourn the senseless loss of George Floyd, and the actions that led to his death are reprehensible and should be condemned in the strongest terms possible,” Abbott said in a statement. “As Texans exercise their First Amendment rights, it is imperative that order is maintained and private property is protected.”

Events late Friday night led police to effectively shut off downtown Houston, Floyd’s hometown. Hearst Newspapers reported that most of the arrests were for obstructing roads. Four officers suffered minor injuries, Houston authorities said. Eight police cruisers were damaged or destroyed.

Floyd died Monday after Minneapolis police officer Derek Chauvin knelt on his neck as he was handcuffed and pleading for air. Chauvin was arrested Thursday on a manslaughter charge.

Ricardo B. Brazziell / Associated Press Austin police arrest a protester as they shut down southbound Interstate 35. Demonstrators were protesting the death of George Floyd.