My neighbour tortures her children, how do I stop her

Parents are supposed to love and care for their children but my neighbour does the opposite. At times I doubt if she is their biological mother.

She starts beating them as soon as they wake up every morning for urinating on bed and throughout the day.

She never allows them play with other children; instead she locks them up in the house.  She even denies them food as punishment for their mistakes.

One day I offered them food because they hadn't eaten for the whole day and to my surprise; she poured it and locked them outside until 8:00pm.

When I asked why she treats her children that way, she told me to mind my own business. I have tried to do so but as a parent, I cannot turn a blind eye. 

Should I report her to the authorities, I feel the urge to do something?

Joyce