A St. Louis County police officer will not face charges for fatally shooting an intruder inside his home.

Prosecutor Bob McCulloch on Thursday provided The Associated Press with his report concluding that the officer acted within the law when he shot 20-year-old Tyler Gebhard on July 9.

The report and police have not named the officer. The shooting happened as he was off-duty at his home in Lakeshire.

The report says Gebhard, who was biracial, and the officer had argued on Facebook about the Black Lives Matter movement. Police say Gebhard broke into the home by throwing a concrete planter through a window, prompting the fatal confrontation.

The document says Gebhard was mentally ill and impaired by marijuana. It says Gebhard and the officer were acquainted through a church group.

ThinkStock