LOS ANGELES, July 5 (Xinhua) -- A magnitude 7.1 earthquake on Friday hit southern California at 8:19 p.m. local time (0319 GMT Saturday), according to the United States Geological Survey (USGS)
The epicenter is near Ridgercrest, a city located 272 km north of Los Angeles downtown. A nearby area was hit by a magnitude 6.4 earthquake Thursday.
Many local residents said they felt the quake. So far, there is no report of casualties.
As the official website of the USGS has collapsed, no detailed information about the quake is available.
The Los Angeles Fire Department has been dispatching vehicles and helicopters around the city to identify any damage or emergency needs, said Brian Humphrey of the department.
"This is part of the same sequence," said Dr. Lucy Jones, a seismologist from California Institute of Technology (CalTech), referring to the quake and the other one in Searles Valley on Thursday, at a press conference which was held 45 minutes after the Friday's quake.
She explained that usually the aftershock would not be stronger, but about 5 percent of the major quakes might be followed by something even bigger.
"Smaller quakes - M5s are likely and a M6 is quite possible," she tweeted after the quake.
It has been the strongest earthquake in southern California since 1999, when a quake jolted the state in the Hector Mines area of the Mojave Desert. No major damage or injuries occurred because of its distance from Los Angeles.