Tasmanian police and firefighters are unable to explain the source of a beam of light which reportedly fell from the sky and formed a circle of fire in a Hobart suburb.

Early Saturday morning police and fire crews received calls from concerned residents in Carnegie Street at Claremont, who reported seeing a bright light igniting a fire in a nearby paddock.

Tasmania Fire Service officer Scott Vinen says the blaze was quickly put out, leaving an obvious burnt patch.

He says the bizarre incident has everyone baffled.

"Once we put the fire out, we kind of walked through the fire and tried to find something," he said.

"We thought a flare or something may have landed there, but we couldn't find any cause."

The Fire Service says it will not investigate further.