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

Police on Wednesday said they charged Michael W. Davis, brother of professional football players Vernon and Vontae Davis, with first-degree murder in the death of Gary Dederichs 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 Washington and hitting them on the head with a hammer.

According to court documents released Thursday, Davis asked a person in his neighborhood how he could buy a gun on at least five occasions in the week leading up to Dederichs’s April 24 death from a head wound in an alley in the 800 block of Emerson Street NW.

The documents did not indicate whether Davis acquired a gun. None of the attacks in which he is charged involved firearms. The witness who told police that Davis asked about guns did not say he sold him one, according to the documents, although he did tell Davis he knew someone who could.

Gary Dederichs, a 66-year-old tourist from Denver who was killed in Petworth in April. (AP)

The same witness, who told police he knew Davis from the neighborhood for several years, said Davis had a history of PCP use, according to court documents. It was unclear from the documents how recently the witness said Davis 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 other court papers. Davis was held for approximately 10 days, according to those documents.

The court papers do not indicate whether Davis displayed any violence last year, only that he needed treatment. They also do not say what happened while he was held.

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

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

Another hearing was scheduled for Friday. Davis has been held and evaluated since his arrest, and the hearing is expected to cover details of his mental condition.

Page, from the District’s Public Defender Service, also indicated that she planned to request a hearing to determine whether Davis is competent to stand trial.