San Francisco's chief of police provided more details Tuesday night about an officer-involved shooting that killed a 28-year-old man at a park in the Bernal Heights neighborhood.

San Francisco resident Alejandro Nieto on Friday night was fatally shot when multiple officers fired at him while responding to reports of a man with a gun at Bernal Heights Park around 7:10 p.m.

Police said officers found Nieto with a weapon and that he pointed the weapon at officers, prompting them to fire at him. The weapon turned out to be a pistol Taser.

"When the officers told him to show his hands, he drew his Taser," San Francisco Police Chief Greg Suhr said. "And as soon as this particular Taser is drawn, it emits a dot, a red dot."

Believing they were in the line of fire, officers started shooting, Suhr said, adding that they kept firing until the red laser was no longer pointing at officers.

Nieto was pronounced dead at the scene, police said.

An angry crowd that attended Tuesday's town hall meeting demanded answers and accountability from the police department. The crowd frequently interrupted Suhr when he attempted to explain the fatal shooting.

Others did not believe the police department's story and called for an outside investigation into the deadly shooting.

Ely Flores, a friend of Nieto, also does not believe the police department's account.

He said Nieto worked as a security guard and was studying criminal justice.

"He knew the law. Somebody who knows the law wouldn't do that," Flores said. "It's just incredible the way they make him look like a criminal. It doesn't make sense."

Family and friends held a vigil for Nieto Monday evening at the site where he was shot, on the north side of the park.

In a poster announcing the vigil, organizers called Nieto, "a joy, a sweet and powerful soul" who was "always with a smile on his face."

Court documents show that a restraining order had been filed against Nieto the day he was killed.

In the filings, a man who said he had once been friends with Nieto claimed he feared for his life and for his wife and three children, ages 3, 4, and 11, because the two had "bad blood."

In a March 14 court record, the man claims Nieto had attacked him with a Taser gun four times, including once in front of his 3-year-old son.

In other documents, the man details experiences of Nieto following him in his car and attacking him with a stun gun.

Tuesday's town hall meeting was held at Leonard Flynn Elementary School at 3125 Cesar Chavez St.

Bay City News Service contributed to this report.