WATCH: Distressing video shows moment thugs burned house in fatal Edenderry arson attack

The 'callous and murderous' attack claimed the lives of 4-year-old Tadgh Farrell and his grandaunt Mary Holt An Garda Síochána have released CCTV footage capturing the distressing moment two thugs threw a petrol bomb through the window of a house in Castleview Park, Edenderry, county Offaly,