National Crime Reports Bureau or NCRB acts as a repository of crimes, as well as criminals to assist the authorities to link the crime to perpetrators. It was setup in 1986 to records data for different categories like Crime Against Women, Crime Against Children, Crime Against SC/ST Population, etc.
Delhi has the highest number of registered cases at 8178, according to the NCRB Report 2015.
Andaman and Nicobar Islands have been ranked 2nd with 86 cases.
Chandigarh has been ranked in the 3rd position with 222 cases.
Sikkim has been ranked at the 4th place with 110 cases.
Please note that it is the Crime 'Rate' and not the highest number of 'Crimes' that is asked in the question.
Hence, while the number of cases may be low in Andaman and Nicobar Islands, it still has the second-highest rate of crime against children.