A moderate earthquake rattled a broad swath of Idaho, damaging property and triggering rock slides near its epicentre in Challis, a city that has endured hundreds of slight to moderate temblors over the last 10 months, authorities said.
The latest measured at a magnitude of 4.9 and was centered about 6.5km from Challis in the state's central mountains, but was felt as far away as Boise, a 305km drive to the southwest, the U.S. Geological Survey said.
The quake caused rock slides, damaged homes and knocked out power around Custer County, local officials said.
Challis Mayor Mark Lupher said he was not in the area when the quake struck, but that authorities told him by telephone that there were no known injuries. Several people living close to the epicentre reported property damage such as cracks in the walls of their homes, he said.
The latest in a string temblors to rattle the area, the quake was more powerful than recent ones, including a 2.9 magnitude quake on December 29, the USGS and Challis Messenger weekly newspaper said.
"We've been around the block a few times," Linda Lumpkin, Custer County Sheriff's Office dispatch supervisor in Challis, said of the frequent seismic activity.
Still, she said, the shaking on Saturday went on for a good nine or ten seconds, leaving people feeling a little rattled.
The dispatch center has been flooded with calls from residents reporting shaking and rock slides, said Lumpkin.
Scientists have been trying to determine whether the quakes, which began in March 2014, have been caused by a known fault thought to be dormant, or are from a previously unknown fault. The earthquakes have been centered near where Idaho's most powerful known quake, measured at 6.9, killed two children in 1983.
Idaho is at the center of a seismic belt that runs from northwestern Montana to southern Nevada and contains thousands of faults in the Earth's crust.
Scientists have said they do not believe the smaller quakes were leading to a larger event in the area.
Claudia Whitten, a glass artist who lives near downtown Challis, said her home shook on its foundation during the 4.9 magnitude event.
"This one really got me. You could feel it in your feet. My whole body was shaking," she said.
Authorities have warned motorists in the area to watch out for falling or loose rocks.
