On Tuesday evening 27 April 2021, unknown offenders unlawfully entered a house under construction located in Wells Parade, Blackmans Bay.
A fire was deliberately lit on the ground floor of the house, which smouldered and caused significant smoke and heat damage.
The fire was not discovered until builders arrived on site early in the morning of Wednesday 28 April.
Damage is estimated to be in excess of $100,000.
Police are seeking any information from members of the public who may observed anyone acting suspiciously in the area.