Childcare operators baffled over two fires in four days

A childcare operator says alleged arson attacks at two centres in less than a week were senseless. (Steven Markham/AAP PHOTOS)

A childcare centre operator is at a loss to explain why two of its facilities have allegedly been set on fire in less than a week.

An automatic alarm alerted authorities to a blaze at Play to Learn Early Learning Centre's facility at Castle Hill, in Sydney's northwest, early on Monday morning.