The 19-year-old District man charged in a recent series of hammer attacks was ruled incompetent to stand trial and will be sent to St. Elizabeths Hospital for an evaluation.

 Michael W. Davis will return to court after 60 days to determine whether his condition improves with medication or other treatment, D.C. Superior Court Judge Robert E. Morin ruled Friday.

Davis, brother of professional football players Vernon and Vontae Davis, is charged with first-degree murder in the April 24 slaying of Gary Dederichs, 66, a tourist visiting from Denver. He also is charged with two counts of assault with intent to kill while armed for allegedly sneaking up on two other people in his Petworth neighborhood in Northwest Washington and hitting them on the head with a hammer.

Morin did not provide details of a sealed report on Davis’s psychological condition, but he said a doctor found that Davis requires treatment and is currently unable to participate in court proceedings. The judge set a follow-up competency hearing for July 13.

During a preliminary hearing that lasted about five hours, Davis spoke only once, saying “How you doing?” when the judge greeted him. Davis sat mostly motionless, his eyes half-shut and fixed forward.

Authorities have said Davis is a suspect in five attacks, including Dederichs’s slaying, but have charged him only in three.

The five attacks, which occurred within a 26-hour period, are similar, authorities said. The victims were struck from behind with a blunt instrument and nothing was stolen. The attacks occurred within a block or so of the 900 block of Emerson Street NW, where Davis lived with his grandmother. One victim described his attacker as being built like a “knock- kneed, high school football player.” Davis is about 6-foot and 200 pounds.

Gabriel Truby, a D.C. homicide detective, testified that medical personnel said Dederichs had several wounds that were circular impressions that appeared to have been caused by a hammer or a baseball bat.

Truby said that one unidentified person said Davis had inquired about buying a gun five times, most recently a week before Dederichs was killed.

Davis was described by people who knew him, according to the detective, as quiet and shy. One said Davis often sat on a brick wall near his house for hours because his family would not allow him to come inside until Davis “calmed down.”

Nearly a year before the attacks, a D.C. Superior Court judge ordered Davis to undergo a psychiatric evaluation, court papers show. The documents do not indicate whether Davis displayed any violence at the time but said he suffered from “auditory and visual hallucinations.” Schizophrenia and “borderline intellectual functioning” were diagnosed preliminarily, according to the papers.

Davis was arrested last week after officers heard a woman screaming. The 20-year-old woman, who was in the 800 block of Gallatin Street NW, had been struck in the back of the head.

When Davis was arrested soon after, his shirt, shoes and jeans were bloodied, authorities said. Police have said they found a backpack that contained a hammer wrapped in a grocery store bag in an alley near Davis’s house.

After his arrest, Davis spoke to the officer in a low voice, saying:“I just want you to know I’m a good person,” Truby testified.

No one from Davis’s family appeared to attend the hearing. His brother Vernon plays for the San Francisco 49ers and his brother Vontae plays for the Miami Dolphins.

Afterward, the mother of the Gallatin Street victim, said she was outraged about the competency finding. “If his family knew he had mental problems, why didn’t they do more to keep him close by? They should have had someone with him 24/7,” she said.