An earthquake of 4.2 magnitude hit about a mile (2 km) north of the Los Angeles community of Pacoima on Thursday, the US Geological Survey said. There were no immediate reports of damage.
Though relatively small in magnitude, the quake, which struck at 4:29 am Pacific time (1129 GMT), was felt in much of the Los Angeles area, social media reports said. A second quake of 3.3 magnitude struck nine minutes later, the survey said.
People on social media reported feeling the quake in areas such as North Hollywood and Sherman Oaks, with some saying they did not receive a #ShakeAlert message on their phones.
"Felt it in Sherman Oaks! Woke us up from a dead sleep. No alert on the phone, though," Twitter user Joe Hubbard said.
Another Twitter user, Lee A Houck, said she received an alert after the shaking began.
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