Southern Regional Safety Officer Barry Gibson said any irregularities observed by residents should be reported immediately to police.
"It is a good time to make sure that there is nothing combustible left outside," he said, urging people to clear wheelie bins, grass clippings and rubbish away from buildings in the area.
Those with unattended holiday homes in Moeraki should inspect their properties to make sure they were secure, he said.
Oamaru detective Warren Duncan was unavailable for comment yesterday, but a media release issued by police on Wednesday night called for assistance from members of the public.
"We would like to hear from anyone who was in the area of Tenby St over those two nights or has any information about the house fires," it reads.
