We report CCD V and I time series photometry of the globular cluster NGC 5024 (M53). The technique of difference image analysis has been used which enables photometric precisions better than 10mmag for stars brighter than V~18.5mag even in the crowded central regions of the cluster. The high photometric precision has resulted in the discovery of two new RR1 stars and 13 SX Phe stars. A detailed identification chart is given for all the variable stars in the field of our images of the cluster. Periodicities were calculated for all RR Lyrae and SX Phe stars and a critical comparison is made with previous determinations.

Cone search capability for table J/MNRAS/416/2265/table2 (General data for confirmed variables in NGC 5024)

Cone search capability for table J/MNRAS/416/2265/table6 (Frequencies and amplitudes of the newly found SX Phe stars)

Cone search capability for table J/MNRAS/416/2265/table7 (Blue stragglers whose variability is to be confirmed)