San Francisco, March 3 (TIWN / IANS) Two US police officers will not face charges for shooting dead Stephon Clark, an unarmed black man, in California last March, prosecutors have said.

Clark, 22, was shot on March 18, 2018, in his grandmother's backyard in Sacramento, the state capital, the BBC reported.

District Attorney Anne Marie Schubert said on Saturday that the officers, who were investigating nearby break-ins, did not commit a crime.

"There is no question a human being died," Schubert told the media after making an apology to the Clark family.

She said that a months-long investigation into the shooting had looked into whether a crime was committed. 

"The answer to that question is no and, as a result, there was no criminal liability."

The use of force was justified, Schubert said, as the officers had feared for their lives, believing Clark was armed with a gun and had allegedly moved towards the officers.

Police body camera and helicopter footage later revealed the officers fired 20 times at Clark, who was then found with only an iPhone, and they waited five minutes before giving him aid.

Demonstrators held protests last month, in anticipation of Schubert's announcement. In the year since Clark's shooting, Black Lives Matter protesters have gathered every week outside the district attorney's office.