The commanding officer of a new D.C. police unit designed to help reduce homicides said yesterday that he is pleased with the outfit's effort during its first two days, despite what he called minor problems.

Inspector Phillip O'Donnell, the commanding officer of the new "rapid deployment unit," said last night that the 100-officer squad had made 18 arrests, mostly on drug charges, during its first two days of operation and had gained information that may lead to an arrest in a homicide case.

Police Chief Isaac Fulwood Jr. announced the creation of the unit last week after a weekend in which nine people were killed in the District.

The unit's main task is to saturate high-crime areas in an attempt to prevent violence. Its officers also help investigators after violent incidents by trying to gather witnesses and other information.

"From what I've seen so far, we have real potential to make an impact," O'Donnell said. "Anytime you do something new, you have minor problems, and it'll take a couple weeks to work out those problems."

Although he did not elaborate on them, O'Donnell said the minor problems the unit has experienced have to do with the fact that there are a number of inexperienced officers on the squad and that some of its members are working in unfamiliar areas.

"We've got guys who're used to the 4th District who we've put in the 7th District," O'Donnell said. "And we're using a lot of young officers. I think as all of us gain experience, we'll be a force to be reckoned with."

Meanwhile, the District's homicide total rose to 384 yesterday when the body of a 17-year-old girl was found in an apartment in the 2500 block of Pomeroy Rd. SE.

The girl had been stabbed several times and apparently had been raped before she was killed, police said. Police officials described the homicide as drug-related.