Fraud jumped 41.9 percent to 75,427 cases in the 11 months through November compared with a year ago, the National Police Agency said.
The NPA said the increase was due to a sharp rise in fraud involving huge cash transfers to banks. Police made no arrests or handed suspects to prosecutors in 95 percent of the cases.
Remittance-soliciting fraud, as it is known by the NPA, mainly comes in three forms, including the "It's me" tactic, which usually involves someone who calls an elderly person, pretends to be a relative and asks for money for some concocted emergency.
The two other methods involve perpetrators demanding a payment for a fictitious reason and money to guarantee a fictitious loan.
A report released Thursday by the NPA says the number of abductions rose 18.1 percent to 287 in the January-November period. Some 43.2 percent of these cases involved victims younger than 13.
The total number of potential Criminal Code violations fell 7.2 percent to 2,365,206 from a year earlier, the agency said.
There were 2,548,761 such cases handled during the same period in 2003, down 2.3 percent from the January-November period of 2002 -- the first decline in eight years.
Of those cases, 624,739 people were picked up or questioned in the 11-month period of 2004 for a rise of 4.6 percent. Arrests and referrals to prosecutors were made in 26.4 percent of the cases, compared with 23.4 percent a year earlier, the report says.
Referring to the two consecutive years of decline in the total number of crimes, NPA Commissioner General Iwao Uruma reckoned that law enforcement authorities have put security in society on the road to recovery.
Cases of serious crimes numbered 20,821, including murder, down 4.28 percent for the first decline in nine years. Street crimes, including vandalization of cars and vending machines, fell more than 20 percent.
Burglary cases rose 9.8 percent to 882.