Demonstrators march in the Texas Capitol on Monday, May 29, 2017, protesting the state’s newly passed anti-sanctuary cities bill in Austin, Texas. Opponents call Texas’ anti-sanctuary cities law a “show your papers” law since it empowers police to inquire about peoples’ immigration status during routine interactions such as traffic stops. (Meredith Hoffman/Associated Press)

AUSTIN, Texas — Hundreds of protesters opposing Texas’ tough new anti-”sanctuary cities” law launched a raucous demonstration from the public gallery in the Texas House on Monday, briefly halting work and prompting lawmakers on the floor below to scuffle — and even threaten gun violence — as tense divides over hardline immigration policies boiled over.

Activists wearing red T-shirts reading “Lucha,” or “Fight,” quietly filled hundreds of gallery seats as proceedings began. After about 40 minutes, they began to cheer, drowning out the lawmakers below. Protesters also blew whistles and chanted: “Here to stay!” and “Hey, hey, ho, ho, SB4 has got to go,” referring to the bill that Gov. Greg Abbott signed into law this month.

Some unfurled banners reading: “See you in court!” and “See you at the polls!”

State House leadership stopped the session and asked state troopers to clear the gallery. The demonstration continued for about 20 minutes as officers led people out of the chamber peacefully in small groups. There were no reports of arrests.

Texas’ new law is reminiscent of a 2010 Arizona “show your papers” measure that allowed police to inquire about a person’s immigration status during routine interactions such as traffic stops. It was eventually struck down in court.

A legislative session that began in January concluded Monday, and the day was supposed to be reserved for goofy group photos and sappy goodbyes. Lawmakers are constitutionally barred from approving most legislation on the last day.

But even after the protest ended, tensions remained high. Rep. Ramon Romero, a Democrat from Fort Worth, said he was standing with fellow Democratic Rep. Cesar Blanco of El Paso when Republican colleague Matt Rinaldi came over and said: “This is BS. That’s why I called ICE.”

Rinaldi, of Irving in suburban Dallas, and Blanco then began shouting at each other. A scuffle nearly ensued before other lawmakers separated the two.

Later, a group of Democratic lawmakers held a press conference to accuse Rinaldi of threatening to…