By Patrick Fallon

EL CAJON, Calif. (Reuters) - Authorities on Friday released two videos of police shooting an unarmed black man dead in El Cajon, California, but the grainy footage, much of it without sound, was not likely to pacify community outrage over the incident.

Police and prosecutors said an investigation was still under way into the fatal shooting on Tuesday of Ugandan-born Alfred Olango, 38, and that no decision had been made on whether to criminally charge the officers involved.

"This is as difficult a situation as any law enforcement officer will ever encounter and it's one we never seek," El Cajon Police Chief Jeff Davis told a news conference. "That being the case, a tragic event took place that took a life and had a major impact on our community."

Video of the incident comes from two sources: A camera mounted at the drive-thru window of the Los Ponchos taco stand in El Cajon and the cell phone of a bystander.

Both videos show two officers confronting Olango in the restaurant's parking lot before opening fire, one with a gun and the other with a Taser. In the bystander video, which lasts only about 17 seconds, a woman can be heard shouting: "Officer don't shoot him!" before at least four shots ring out and she screams.

Olango's actions in the moments before he is shot are difficult to make out, in part because he is obscured at times by an officer.

Family members and activists have called for several days for police to release the video, believing it would show that officers acted improperly. Olango's mother, during an emotional news conference on Thursday, said that her son was having a mental breakdown and that police should have helped him instead of quickly opening fire.

An attorney for the family, Dan Gilleon, said on Friday that the newly released footage supported their position that the officers had "provoked a mentally disturbed person".

The tragedy has drawn attention in Africa, where officials from several countries criticized Olango's death and a string of police killings of black men in the United States.

The shooting has also led to protests in El Cajon, a suburb of San Diego, where on Thursday night police used pepper spray to disperse the crowd and arrested two men for unlawful assembly.

On Friday night, about 200 protesters held a peaceful demonstration, marching and chanting "no justice, no peace," near the scene of the shooting. Leaders of the demonstration pushed protesters back onto sidewalks and away from police in riot gear in an attempt to keep the demonstration peaceful and orderly.

"We don't want war, we want to be heard," one of the leaders said to fellow demonstrators.

Activists and Olango's family have criticized authorities for previously releasing a still photograph of him pointing an object at an officer, saying it gave an unfair impression of the former Ugandan refugee.

El Cajon officers Richard Gonsalves and Josh McDaniel, both 21-year veterans, were responding to emergency calls about a "mentally unstable" man walking in traffic, officials said.

Police have said Olango ignored commands to take his hand out of his pocket before pulling out an object later determined to be a vaping device used to inhale nicotine. Olango assumed a "shooting stance" and pointed the device, which had a 3-inch-long (8-cm) cylinder, police said. No gun was found at the scene.

Gonsalves opened fire and McDaniel discharged a Taser device, police said. Police have not said how many shots were fired. A family spokesman said Olango was shot five times.

The officers have been placed on administrative leave during the investigation.

(Reporting by Patrick Fallon in El Cajon, Ben Klayman in Detroit and Dan Whitcomb in Los Angeles; Writing by Dan Whitcomb; Editing by Cynthia Osterman, Lisa Shumaker and Christian Schmollinger)