Prosecutors will not press charges against a security guard who shot and killed Banko Brown, who was suspected of shoplifting at a Walgreens in downtown San Francisco last month, the district attorney's office announced Monday.

Surveillance video and other materials regarding Brown's death were released Monday following an investigation by the district attorney's office due to the "extraordinary public interest" in the case, the San Francisco DA's office said in a statement.

"Based on the criminal investigation, review of evidence, and evaluation of the case, we have determined that there is insufficient evidence to support the filing of criminal charges against the suspect in the Banko Brown death investigation," the statement said.

The San Francisco Board of Supervisors last week sent a letter asking District Attorney Brooke Jenkins to release the surveillance video showing the April 27 shooting after no charges were brought against the guard during the 72 hours he was in custody.

The surveillance camera video released Monday shows Brown attempting to leave the store before the security guard, identified by police as Michael Anthony, stops him. Brown then shoves the guard, leading to a physical altercation. Brown is held on the ground by the guard but released after about a minute, the video shows. Brown starts to leave but appears to turn around and move toward the guard who then shoots him, the video shows.

According to the district attorney's report, Brown was a transgender man.

In his videotaped interview with police, Anthony described what happened, after Brown started to leave.

"She turned back around and advanced toward me," he said, using incorrect pronouns in reference to Brown.

"And I didn't know what she was planning on doing, but, uh ... turns out her intention was to ... try to spit at me and by that reaction by her turning around and advancing towards me ... that's when I lifted it (motions with hands) and then shot once."

John Burris, an attorney representing Brown's family, said he will move forward with filing a lawsuit in the case soon.

"I've seen the tape and looked it over pretty closely and I believe this shooting death was unjustified," he told CNN.

"The family is very disturbed that no prosecution has taken place, particularly the father and the mother, and they would like the matter to be sent to the attorney general's office for review."

San Francisco Board of Supervisors President Aaron Peskin said he is asking the state attorney general and the US Department of Justice to review the case.