24 3) image data is deleted three years after the end of the validity period of the administrative authorization or decision granted by the police for the preparation of which the personal photograph and specimen signature were last used; 4) local police background check data is deleted one year after a new limited background check is conducted, but in any event no later than ten years after the check; 5) aliens identification data is deleted ten years after its recording; however, if the data subject has obtained Finnish citizenship, the data is deleted one year after the file keeper was informed of the Finnish citizenship in question. (2) All data on a person held in the data system is, however, deleted no later than one year after the data subject’s death, unless there is a special reason for retaining the data. The need to retain the data is, however, reviewed no later than five years after the previous occasion on which it was reviewed, and an entry is made accordingly. Section 24 Deleting data from the Suspect Data System (1) Data in the Suspect Data System is deleted ten years after the last entry was made for the suspected offence. Section 25 Deleting data from the Operational Data System of the Security Police (1) Data on a person held in the Operational Data System of the Security Police is deleted 25 years after the last data entry was made. Data in the data system concerning basic background checks and extended background checks is deleted within one year of conducting an equivalent new background check, but in any event no later than ten years after the check. Section 26 Deleting data from other personal data files