MINNEAPOLIS, April 29 (UPI) -- A minor earthquake rattled western Minnesota early Friday, the U.S. Geological Survey said.
The quake measured 2.5 on the Richter scale, the Minneapolis Star Tribune reported. The epicenter appeared to be on the edge of the town of Alexandria, near the airport.
John Bellini, a geophysicist with the survey, said about 20 people reported feeling the quake. There were no reports of damage.
"I happened to be in bed awake," said Sandy Pederson, a staffer with KXRA-AM in Alexandria. "My first thought was that it was thunder."
She said the radio station got a lot of phone calls about the shaking from Alexandria and its immediate area. A few callers said they noticed slight movements in ceiling tiles.
There are about 1,000 earthquakes in the 2.0 to 2.9 range every day worldwide. They generally do no damage and often are not felt, although they are picked up by seismographic equipment.
The largest recorded quake in Minnesota occurred in 1975 and measured 4.6 on the Richter scale. The quake caused minor damage around the town of Morris.
The most recent recorded quake was in 1994 and measured 3.1.