German police officers in the northern city of Hanover are using Facebook to catch criminals in an experiment that might be expanded to other forces in the country. Six months\' ago the Hanover police force set up a Facebook account with appeals to the public to come forward to help solve cases.This has already led to the clearing up of six cases, including one break-in, one auto theft, and one missing person. The \"Polizei Hannover\" Facebook account already has some 23,000 \"friends\" who pass on information to their own contacts, said police spokesman Stefan Wittke. This has resulted in over 1.6 million \"hits\" on the police account in the past month, he added. \"With Facebook we can reach quite a different audience than that of newspapers or television. Seventy percent of our Facebook fans are aged under 35,\" according to the police. \"And, statistically speaking, the vast majority of people involved in violent crimes are young -- whether they be victims, offenders or witnesses. In other words, with Facebook we can reach exactly the right target group.\"On Thursday, the Facebook page gave information about the arrest in Poland of a man wanted in connection with a robbery in Hanover, and published video surveillance photos of several men, including one wanted for attempting to rob a 71-year-old woman, and two showing armed men robbing a petrol station. Police also herald some of their recent successes, including the corralling of two elephants who had escaped from a zoo.If considered to be successful, the six-month experiment, which ends later this month, might be extended to other police forces in the country, added Wittke.