Two young Washington men have been arrested and charged with homicide in the death of a 20-year-old Howard University student who was killed March 26 in a robbery attempt outside his dormitory, D.C. police said.

Police said the two arrests followed the recovery on March 30 of the gun said to have been used in the fatal shooting of the student, Blaine W. Pitts, a junior from Dover, Del.

Pitts was shot about 1 a.m. in his car at Second and Elm Streets NW outside Carver Hall after two men approached the vehicle and anounced a robbery, police said. According to police, Pitts was shot in the chest after refusing to surrender his wrist watch. Another student who was wounded in the incident has recovered, police said.

Four days after the shooting, police said, a gun taken from a man who came to the attention of police after an altercation. According to papers filed in court here, the gun was later identified as having been used in the shooting of the student.

Information developed after recovery of the gun led police to the names of two suspects, according to a court affidavit.

Police said they arrested Charles M. Barksdale, 21, of 1835 Sixth St. NW about 9:40 p.m. Friday. The next day, police said, Ernest K. Jones, 19, of 1900 Ridge Pl. SE, was arrested at the Sixth Street address. Both were charged with homicide in the shooting of Pitts, police said.