PLEINE-FOUGERES, France (AP) _ All but one young man in a rural French village gave DNA samples to help solve the murder of a 13-year-old British girl during three days of tests ending Sunday.

Saliva samples were collected voluntarily from 169 of the 170 men between the ages of 15 and 35 in the village of Pleine-Fougeres to determine whether one of them raped and killed Caroline Dickinson on July 18, 1996.

It was unclear why the last man in the age category did not get tested.

Investigators say there is no evidence the killer comes from Pleine-Fougeres, a village of about 1,800 people in western France, or is in the age group being tested. They believe the tests could eliminate a large group of possible suspects.

Philippe Drouet, one of the prosecutors, said the results could be known by Friday after police laboratories determine if the samples collected match those found on the victim.

Caroline Dickinson, who was on a visit to France with schoolmates, was raped and strangled in her youth hostel bed.

The mass testing stems from efforts by her father, John, who pressed for the measure and got the judge in charge of the case replaced when he balked at the idea.

If the murderer is not found among the group tested, men from Pleine-Fougeres between the ages of 35 and 60 will be asked to give a saliva sample in November.

Though rare, DNA testing of an entire town has been tried in Britain with some success. In Wales last year, a killer was caught in just such a roundup. The process is not used in the United States.

Christian Couet, the mayor of Pleine-Fougeres, congratulated the village for its cooperation.

Fear of suspicion and ostracism may be key factors that drive people to volunteer for testing.