Two women defied a centuries-old ban on entering a Hindu temple in India's southern state of Kerala in the early hours of Wednesday, the state's chief minister said, raising fears of a backlash from conservative Hindu groups.

The women, reported by Reuters partner ANI to be in their 40s, entered the premises of the Sabarimala hill temple, defying local tradition that bars women of menstruating age — between the ages of 10 and 50.

Conservative Hindu groups say they believe women of menstruating age would defile the temple's inner shrine. Local news channels reported the chief priest closed the temple for "purification" rituals after the women visited.