Three people were killed and four others were injured in a shooting at a bowling alley in Torrance, Calif., late Friday night, the police said.

The Torrance Police Department responded just before midnight to reports of shots fired at Gable House Bowl in Torrance, which is about 20 miles from downtown Los Angeles.

Three men were pronounced dead at the scene, the police said, and four more were injured. Two were taken to the hospital, and the others sought medical attention on their own.

A police spokesman said information about a suspect or motive was unavailable. The police did not identify the men who died.

One of the victims was identified by his sister as Michael Radford, 20.

The sister, Latrice Dumas, said she was at the movies when her family called and said her brother had been shot. Ms. Dumas, 28, said she heard Mr. Radford was trying to protect his girlfriend, who had been accosted at the bowling alley.

“He always felt like he could be a protector,” Ms. Dumas said.

She said his death was “tearing” her family apart. Mr. Radford grew up in Los Angeles, and worked in construction, she said, adding that he wanted to be an auto mechanic or a mathematician.

She said he had a 7-month-old daughter.

“Who did this to my brother?” she asked. “It’s just crazy.”

Wesam Hamad, 29, was bowling with his 13-year-old niece and 32-year-old cousin near the entrance of the alley. He said a fight broke out within a group of about 10 men and women behind their lane, near the desk where bowlers check in. Mr. Hamad said there was a small arcade there, and he heard someone slam into one of the machines.

He told his niece to leave and as they were walking, they heard a series of about 15 gunshots. He ran to the other end of the alley with his niece and his cousin, and they dove behind some couches.

“I still had my bowling ball in my hand. I held my bowling ball behind my niece’s head just in case something ricocheted,” Mr. Hamad said. “We’re just lucky to be alive. I’m still in shock.”

Gable House Bowl did not immediately respond to a request for comment. The bowling alley offers glow bowling and laser tag, according to its website. The police said no bowling alley employees were injured.

The shooting set off renewed discussion about gun violence, as shootings continue to take place in public spaces, even in California, which has among the toughest gun laws in the nation. In November, a gunman set off smoke bombs and opened fire at a country-music bar, the Borderline Bar & Grill, in Thousand Oaks, Calif., killing 12 people.

Senator Kamala Harris, a Democrat of California, said in a tweet that she was heartbroken for the victims of the bowling alley shooting and their loved ones.

“We must do more to address gun violence,” she said. “Americans should be able to go to a bowling alley and be safe.”

Damone Thomas said in a Facebook video that he witnessed the aftermath of the shooting. He said he was enjoying karaoke when he said people rushed into his area and shouted “gunshot, gunshot, gunshot, gunshot.”

“To realize that the space was invaded, just by one simple thing: a gun,” he said. “How do we get over this? Where can we go? We see it happening in the church, we see it happening in the schools, now it’s happening in the karaoke. It’s happening everywhere, so what can we do? Where can we go?”