TULSA, Oklahoma - Three north Tulsa house fires strained the fire district's resources overnight Saturday, authorities told News On 6.

Two of the fires, at unoccupied houses, are under investigation.

A neighbor called in reporting a house fire at a single-story wood frame house in the 1900 block of East 26th Place North at about 2:45 a.m. Tulsa resident Kejuan Oliver said he smelled smoke for a while before going outside to investigate.

Oliver found the abandoned house next door in flames.

Tulsa fire crews arrived to find the house fully engulfed in flames, according to District Chief Eddie Bell with the Tulsa Fire Department.

Bell said the fire may have started on the front porch which collapsed from the flames. The structure was a total loss, he said.

Tulsa firefighters responded to another blaze at an unoccupied house in the 800 block of North Evanston. That fire took place just after 3 a.m.

Someone was seen fleeing the scene of the fire as firefighters arrived, according to Tulsa District Fire Chief Michael Atchison.

The house is for sale, and utilities were still connected. Crews were able to knock down the fire pretty quickly.

The third fire was just before 2 a.m. in the 4200 block of North Hartford. That home was occupied, but there were no injuries.