Prince William County law enforcement officials often shake their heads at the oddness of some of the crimes that occur in their community.

Although the crime rate is relatively low -- there were only four murders last year, for example -- the nonviolent incidents often have an offbeat or humorous twist and violent crimes frequently are unusually cruel, according to police.

"We get a lot of bizarre crimes, there's no doubt about that," said Sheriff Wilson Garrison, a former county police investigator. "I don't know what turns Prince William County."

Consider:

Jennifer Au made national headlines in 1988 when she went to jail for five days on a contempt charge when she refused to disclose the whereabouts of a sable-colored slinky ferret named Fuji, who was accused of biting a 5-year-old boy in a Manassas pet store. Meanwhile, the child underwent several rabies treatments because doctors could not determine whether the boy was infected without testing the animal.

A 100-pound cement kangaroo was stolen from an apartment in Woodbridge several years ago and a 46-inch plastic Santa Claus was stolen from a front yard in Dale City in December 1987. The Santa Claus was returned four months later after the owner received a letter containing a photo of Santa living it up in sunglasses on some unknown beach. The kangaroo culprit was caught; the Santa stealer skipped.

Pranksters, believed to be students from a medical lab, left a human arm on the front porch of a Woodbridge McDonald's restaurant around Christmastime in 1987, with the palm facing upward as if reaching for the door handle. Police, who found another arm in a gutter a few days later, said the limbs appeared to have been removed during a laboratory procedure. No one was arrested in connection with the incidents, county police spokeswoman Kim Chinn said.

"We have some unusual people out here," said Commonwealth's Attorney Paul Ebert, who has prosecuted more than 4,000 cases since he took office in 1968. "Truth is stranger than fiction, they say, and that is particularly true in this county."

Prince William has no monopoly on weird crimes, however. "Those things don't happen here any more than they do any place else," county Police Chief Charlie T. Deane said. "But since we are smaller and a little further out, they get more attention than they might in Washington."

Police, lawyers, residents and social scientists say there is no explanation for the unusual events, but they said the incidents in Prince William could possibly be attributed to several factors: a largely transient population; a frontier-like spirit of "rugged individualism"; a lack of strong community ties by many who work and socialize outside the area; stress from commuting; and boredom.

Ebert attributed the visibility of some of the cases to zealous investigation by the Prince William police, who take the time to investigate crimes that might be placed on a back burner in larger, more urban jurisdictions in the area.

Prince William's population grew by 55 percent between 1980 and 1990 to 230,000, as people moved in to take advantage of the county's more affordable housing. "We have a high transient population and not as affluent a population as most other metro areas, particularly in Northern Virginia . . . and that may lead to some of these unusual situations," Ebert said.

Lon Farris, who has served as defense counsel for several of the county's more publicized crime suspects, said the population explosion has eroded the county's sense of community, making people less likely to think twice about breaking the law.

Prince William's unusual crimes haven't gone unnoticed by people who live outside the county.

Farris said he is often asked about some of the more unusual cases when he meets with lawyers from other communities. "People seem to ask about the more high-profile cases," Farris said. "It's not like Prince William County is the crime capital of the world, because it's a safe place to live. But the crimes we get, they seem to be on the strange side."