A magnitude-7.3 earthquake struck dozens of miles off the coast of El Salvador on Monday night, the U.S. Geological survey said.
There was no threat of a tsunami along the California and Central American coasts, according to the National Tsunami Warning Center in Arkansas and the Pacific Tsunami Center.
The temblor struck 53 miles south southwest of the coastal town of La Union about 8:51 p.m. PT at a depth of about 25 miles, the USGS said. Initial magnitude was measured at 7.4, but that figure was later revised to 7.3.
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The USGS initially reported that a second quake of the same magnitude had registered a minute later in the same area, but that entry was later removed from the agency's website.
It was unclear if there were immediate reports of injuries or damage.
Power outages have been reported in El Salvador. Nicaragua put out an internal alert, announcing that schools would be closed on Tuesday. Local reports say tremors could be felt along the southern coast and interior of the region from Guatemala to Costa Rica.
The Red Cross in El Salvador and Costa Rica, the two countries closest to the epicenter, had no reports of victims.
The quake occurred in a "very seismically active" area, according to the USGS. Earthquakes of magnitude 7.3, 7.7 and 7.3 have occurred within 130 miles of Monday night's quake. The Cocos and Caribbean plates converge in the region, which saw significant damage and fatalities due to a landslide after a magnitude-7.7 quake in 2001.
That earthquake triggered aftershocks, including one of magnitude-6.6 near San Salvador.
NBC4's Jonathan Lloyd contibuted to this report.