INDIANAPOLIS - Indianapolis firefighters were busy Monday morning battling an outbreak of fires, including three within blocks of each other on the city's east side.

Investigators are looking at the cause of five fires that broke out overnight.

Of the three on the east side, the first was reported in a vacant house in the 300 block of South Rural Street just before midnight.

Two hours later, firefighters were called to a blaze in a vacant home in the 800 block of South Rural Street.

"I came out of my house as the firefighters were entering the property with chainsaws to cut through the roof," a witness said. "I did see extremely large flames in the back of the house and coming out of the back of the house."

About 30 minutes after that, a fire was reported in a home on South East Street, just a block away from the second fire.

A family of five was forced out of their home in the blaze, and firefighters were called in from other districts to help battle the heavy flames.

The other two overnight fires were reported on opposite ends of the city.

Investigators have not determined if any of the fires were intentionally set or if they may be connected.

No injuries were reported.