According to the Sacramento Bee's Nashelly Chavez and Jose Luis Villegas, demonstrators were protesting the fatal police shooting of Stephon Clark. The event started on Interstate 5 before moving in front of Golden 1 Center.
In response to the demonstration, the Kings locked the arena entrance doors and ordered security inside the arena.
"Tonight's game began with a delay," the Kings said in a statement, per the Sacramento Bee's Jason Jones. "Due to law enforcement being unable to ensure ticketed fans could safely enter the arena, the arena remains closed and we ask fans outside to travel home. We will issue further information soon regarding a refund."
Kings owner Vivek Ranadive offered a statement of his own after the game:
"We had multiple conversations during the game about it," Kings swingman Vince Carter said of the protests, according to the Sacramento Bee's Jason Jones. "And when I say we, I mean both teams, with each other. We have a game to play, we have a job to do but it didn't go unnoticed."
Scenes of the protests began surfacing on social media:
The game was originally scheduled to start at 10 p.m. ET, but the opening tipoff wasn't until 10:23 p.m. ET, according to ESPN.com. With the lengthy delay, the arena scrapped the traditional player introductions prior to the game, per Deadspin's Timothy Burke.
Ezra David Romero of Capital Public Radio reported arena personnel allowed the fans in attendance to sit in the lower bowl and provided free refreshments.
Jones showed what the Golden 1 Center looked like inside when the action got underway:
The Associated Press' Sophia Bollag and Don Thompson reported the protests began at city hall in Sacramento before crossing the highway and winding back downtown.
CNN's Eric Levenson, Madison Park and Darran Simon reported Clark died Sunday night after being shot multiple times by police officers in his grandmother's backyard. Officers said they believed Clark was in possession of a firearm at the time of his shooting, but investigators didn't recover a weapon at the scene.