The quiet Texan farming community Stephenville is being gripped by UFO fever after a string of sightings.

Dozens of people - including a pilot, county constable and business owners - insist they have seen a large silent object with bright lights flying low and fast.

Some even report seeing fighter jets chasing it.

Local newspaper reporter Angela Joiner said she had received loads of emails about it.

"It is the talk of the town right now," she said.

Stephenville officials insist there is a logical explanation but the locals swear that it was larger, quieter, faster and lower to the ground than an airplane.

A spokesman for the nearby Joint Reserve Naval Air Station said aircraft from his base were in the area on the night of January 8 when most people reported the sighting.

But he did say the object may have been an illusion caused by two commercial airplanes.

About 200 UFO sightings are reported each month, mostly in California, Colorado and Texas.

Fourteen per cent of Americans surveyed last year say they have seen one