Gary Dederichs, 66. (AP)

The 19-year-old District man charged with killing a 66-year-old tourist from Denver sought to buy a gun in the week before the attack, according to court documents.

 Police on Wednesday said they charged Michael W. Davis, brother to professional football players Vernon and Vontae Davis, with first-degree murder in the death of Gary Dederichs, 66, of Denver.

Davis has also been charged with two counts of assault with intent to kill while armed for allegedly sneaking up on people in his Petworth neighborhood in Northwest and hitting them on the head with a hammer.

According to court documents released Thursday, Davis asked a person in his neighborhood if he could buy a gun from him. That person did not sell him one, according to the documents, though the person did say he told Davis he knew someone who could sell him a gun.

It is not known whether Davis ever obtained a gun, though none of the attacks he is charged in involve firearms.

The same witness told police Davis had a history of PCP use, according to court documents. It was unclear from the document how recently the witness said he had used the drug.

Davis was held for psychiatric evaluation a year ago after his teachers and guardian became fearful of his behavior, according to documents filed in D.C. Superior Court.

During a Thursday hearing, defense attorney Dana Page argued that the witness came forward after Davis had been arrested and only provided information that had already been printed in the media with regard to the alleged attacks.

Police were investigating five total attacks, including the fatal beating of Dederichs.

This item has been updated.

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