SARNIA, ONT. -- Sarnia Fire and Rescue officials are investigating two separate early morning structure fires on the same street.

Fire crews were called to Lanark Court just before 4:30 a.m Tuesday for reports of a structure fire.

When fire crews arrived, they noticed one townhome engulfed in flames, and a second town home just a few doors down was also on fire.

Police say both residences were unoccupied at the time with no injuries being reported.

Sarnia Fire Safety educator, Officer Mike Otis, says the two fires are under investigation by the Ontario Fire Marshal's Office.

“These two fires were separate based on their distance burnt unit is here and the other one is actually facing the other direction, quite a distance apart. It wouldn’t be a typical exposure type situation,” says Otis.

The first townhome along the side of Lanark Court is demolished, and the fire also caused damage to neighbouring townhomes.

The second townhome, in the middle of Lanark Court, police say is a basement fire with minimal damages.

On Monday, Sarnia Fire battled two structure fires simultaneously, one fire destroyed three units in a townhome on Kathleen Avenue and the second fire destroyed a home on Rayburne Avenue.

All four fires are currently under investigation