A 3.9-magnitude earthquake struck near Lake Elsinore in Riverside County on Thursday morning, felt by residents across San Diego County and as far as Pasadena. The quake, occurring at 9:39 a.m., was followed by a 3.0-magnitude aftershock less than a minute later, with no reports of damage. In a separate incident, a 4.4-magnitude quake rattled the Los Angeles area on Monday, causing some minor disruptions but no major injuries or damage. Notable effects included a burst pipe at Pasadena City Hall and interruptions during live broadcasts, with reports of shaking felt down to San Diego. Local authorities conducted assessments and found no significant structural damage in Los Angeles. The seismic activity highlights California's vulnerability to earthquakes, prompting reminders for safety measures during such events.