The earthquake happened around 1:35 a.m. PST, and a 2.3-magnitude aftershock took place at 2:07 a.m., the U.S. Geological Survey said.
The epicenter was 3 miles north of Fontana and 46 miles east of Los Angeles.
Police said there were no reports of damage or injuries, or requests for emergency aid, KTTV-TV, Los Angeles, reported.
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