Five others were freed subsequently.
In addition, three persons are still reported as missing.
Most of these kidnappings had been committed by armed men who had come in white vans.
Among the abducted persons are social activists, businessmen, persons police describe as underworld members and the witnesses in the Bharatha Lakshman Premachandra murder case.
Political activists Lalith Kumar Weeraraju and Kugan Murugananthan were abducted in Jaffna on December 09, while a suspect in a court case, identified as Mervyn, wsa kidnapped in front of the Hulftsdorp court complex.