By David Mercer, news reporter
A powerful aftershock has hit Southern California following the US state's strongest earthquake in 20 years – amid warnings an even bigger seismic event could be about to strike.
The 5.4-magnitude tremor – one of more than 80 aftershocks so far – was recorded in the early hours of Friday in the same desert region as Thursday's 6.4 quake.
It comes after a "swarmaggedon" of 1,000 small tremors were felt in California last month, with experts warning that more quakes – including potentially bigger ones than Thursday's event – are likely.
"This does not make [the big one] less likely," seismologist Lucy Jones told the LA Times.
"There is about a one in 20 chance that this location will be having an even bigger earthquake in the next few days, that we have not yet seen the biggest earthquake of the sequence."
Witnesses described items falling off shelves "like missiles" during Thursday's quake which "wouldn't stop" rattling buildings and cracking road surfaces.
Hollywood superstars were among those who reported feeling the effects of the powerful tremor which struck near the town of Ridgecrest, about 150 miles northwest of Los Angeles.
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Multiple injuries and two house fires were reported in the town, while emergency workers dealt with gas leaks and reports of cracked roads.
A state of emergency was declared in California's Kern County and people in Ridgecrest Regional Hospital had to be evacuated.
Dr Jones said the quake was on a "strike-slip fault" about 10 miles from Ridgecrest and not on the dangerous San Andreas fault.
It was shallow at only 6.7 miles deep – amplifying its effect – and was felt in an area inhabited by 20 million people, the European quake agency EMSC said.
April Rodriguez, who lives in the town of Trona, said she felt a smaller quake followed by a larger one "that didn't stop".
"We were panicked trying to get out of the house because everything is falling out of the cabinets, off the shelves, off the walls… they were flying like missiles off the shelves," she told CNN.
The 6.4 quake reportedly hit as children were putting on a Fourth of July performance at Burroughs High School in Ridgecrest.
"The kids were crying and scared," Vicki Siegel told the LA Times.
"I don't know what kind of damage was done inside the building but we all got out. They probably all have PTSD now."
Cynthia Alvarez, who works at a hotel in El Segundo, told the newspaper: "IRead More – Source