SAN FRANCISCO -- After five days of heat over the fatal shooting of a fleeing suspect in the Bayview, San Francisco police on Thursday let loose a bombshell - the young man not only had a gun, officials said, but appears to have killed himself with it.

The bullet that killed 19-year-old Kenneth Wade Harding on Saturday came from a .380-caliber firearm, authorities announced, and a round of the same caliber was recovered from Harding's jacket pocket.

San Francisco police officers, by contrast, are armed with .40-caliber ammunition and guns that can't fire a .380-caliber shot, said John Sanchez, a firearm supervisor with the Police Department crime lab.

Cmdr. Mike Biel, who heads investigations, said detectives now believe Harding fatally wounded himself as he fled from two police officers who were attempting to check whether he had a Muni ticket.

Police are still trying to find that weapon, which they believe was stolen from the crime scene.

"Based on the findings of the medical examiner, at this time we believe he was fatally wounded by a .380-caliber bullet," Biel said Thursday afternoon at the medical examiner's office, which is rarely the site of news conferences.

Accidental or intentional

"We believe the fatal wound to Mr. Harding's body was self-inflicted," he said. "The investigation is still ongoing as to whether or not this was accidental or an intentional act."

Police said earlier that Harding tried to shoot at the two officers during the chase. Still, the death of Harding, a Washington state parolee wanted for questioning by Seattle police in connection with a July 13 killing there, sparked outrage in the Bayview district.

'Spirit of transparency'

In an attempt to quell that anger, San Francisco police have spent the week releasing fresh information on the investigation as it becomes available. Biel said Thursday's announcement is an attempt to maintain that "spirit of transparency."

Police officials sat alongside Chief San Francisco Medical Examiner Amy Hart as she announced the preliminary findings of Harding's autopsy. She said Harding was struck by two bullets, one of an unknown caliber that entered and exited his left leg and the .380 caliber one that entered his neck and lodged in his head.

While his cause of death has not been officially determined, Hart said in response to a question that it is "correct" to assume Harding died from the shot to the head.

Earlier this week, police said lab tests revealed gunshot residue on Harding's right hand, and that ShotSpotter, a gunshot detection and location system, showed that three guns were fired during a six-second period.

A total of 10 shots were recorded, police said - a first shot, followed by a 1.9-second pause, then nine more shots in rapid succession.

Police were unable to find a gun at the scene, but video taken by a bystander shows an object on the ground roughly 10 yards from where Harding fell wounded. Biel said a man in a hooded sweatshirt picked up a gun, shell casings and a cell phone and spirited them away from the scene.

Acting on a tip, police seized a gun from a parolee's home not long after the incident. But Thursday, Biel said that gun was a .45-caliber and is not the same one Harding fired.

Reward for finding gun

He asked for the public's help to find Harding's firearm, and said police are offering a $1,000 reward. Biel also said investigators are still trying to locate the man in the hoodie.

Harding was released on parole in April in connection with charges that he tried to force a 14-year-old girl into prostitution in Seattle, and police there said he is also a person of interest in a shooting that killed 19-year-old Tanaya Gilbert and wounded three others.

The fatal shooting of Harding on a crowded street in broad daylight has angered many people. Some have said they don't believe he was armed, while others have complained of a long history of poor relations between police and San Francisco's African American community.

On Tuesday, 43 people were arrested during a protest that led to vandalism of a Muni station and, according to police, two assaults. On Wednesday, Police Chief Greg Suhr was booed offstage during a town hall meeting at the Bayview Opera House.

Biel said Thursday that he understands there may be skepticism about the latest evidence revealed by authorities. He asked the public to keep in mind that it is the result of investigations by the civilian medical examiner and the firearms unit of the city crime lab.

"Our investigation is based on total facts," he said.