According to a phone interview conducted by ABC News, a young university student who was not involved in the protest said he witnessed what appeared to him to be multiple arrests.

"It looked like their hands were tied," the student told ABC News, adding that they were probably "tied with zippers."

The student described protesters being surrounded on both sides by mounted police and state troopers dressed in riot gear.

In a separate phone interview with ABC News, the Austin Police Department said its role is only to assist the UT Police Department, the main agency responding to incidents on campus; they do not register individuals.

Public support for students protesting for Gaza at Columbia University Public support for students protesting for Gaza at Columbia University

The Texas Department of Public Safety also assists the UTPD, APD said.

The Daily Texan, the school's newspaper, reported that about 50 state troopers were seen in riot gear and issued a two-minute warning for protesters to disperse.

The crowd is estimated at 150 to 200 people.

This is a breaking news story. Return to this post for more updates.