SOUTH BEND, Ind. –The South Bend Fire Department is responding to a fire at Franklin and Calvert Streets.

The fire caused a building to collapse and then spread to two other buildings. 

One of the buildings was formerly a factory occupied by a tire business.

Firefighters are working to contain and extinguish the fire. The call came in at 5:10 p.m. on Sunday.

The department is characterizing the fire as a "defensive fire," meaning that they have not been able to enter the building.

One firefighter was treated for heat exhaustion.

It is still not know what is inside of the building.

No injuries are being reported.

All three buildings are abandoned.