Just halfway into the year, Fairfax County police are investigating their 10th homicide, the same number that occurred in all of 2004 -- and the year before.

But law enforcement officials say the county's homicide rate, like the rest of the nation's, has been falling in recent years and it is too soon to tell if that is about to change. In 2002, there were 21 slayings in Fairfax, still considered an extraordinarily low number in a county with more than one million residents.

Police say most of this year's slayings were the result of domestic disputes or involved people who knew one another, as they were in previous years. Although four of this year's slayings remain unsolved, police said most of those in which arrests have been made have not been concentrated in a few crime-ridden areas or related to gangs or drug rings.

"We in Fairfax County will keep monitoring what the numbers are," said Lt. Richard Perez, a police spokesman. "We're only halfway into the year. I hope we have no further incidences of homicides. . . . I think it's too early to say anything beyond that."

The latest slaying occurred shortly before dawn Saturday. Police found the body of Jack S. Cornejo, 23, in the courtyard of a Fair Oaks apartment complex. He had been shot after fighting and struggling with another person, Perez said.

Investigators have identified and questioned the alleged shooter.

Police said they are not pleased with the pace of homicides but said there is no cause for alarm.

Some county officials emphasized that each slaying must be considered individually.

"There's always cause for concern . . . but most of them are something that happened in a neighborhood, related to families," said Supervisor Elaine N. McConnell (R-Springfield), in whose district the two most recent homicides occurred. "I don't feel like it's outside crime coming in. That makes us feel a little better."

McConnell said she is confident that police are working hard to prevent and solve homicides. She said she had not heard complaints from constituents.

This year's homicides include the March 24 slaying of Kiran V. Kadian, a Great Falls woman whose son was later charged with murder, and the Feb. 13 shooting of Annandale resident Michael Kenagy, whose roommate was charged. Earlier that month, Marcos E. Gonzales-Reyes of Falls Church was charged with killing his girlfriend.

Police have deemed one slaying this year -- the January shooting of Anthony Campos, 15, of Arlington -- as gang-related. Police have said they believe he was mistaken for a rival gang member because of his clothing.

Perez said police do not know if Cornejo knew his killer. Police arrived at the apartment complex, in the 12000 block of Pender Creek Circle, about 4:50 a.m. Saturday after callers said they heard a fight and possible gunshots. Cornejo's body was found in the courtyard, where police believe the shooting took place, Perez said.

Cornejo's family could not be reached to comment yesterday.

Charges could be forthcoming depending on autopsy results, said Fairfax Commonwealth's Attorney Robert F. Horan Jr. He said he would consider whether the alleged shooter -- whose name police have not released -- acted in self-defense.

Horan, the county's prosecutor for nearly four decades, said he does not believe that the number of homicides this year is "significant."

"In so many places, you've got some stranger attacking someone -- those are the cases that give me concern," Horan said. "But the domestic ones, they tend to happen. There's no way for us really to do much to prevent those."