USGS: Mysterious 'Non-Earthquake Event'

The agency said its app development team was working to make improvements to the system based off what they learned from this event.

Asked whether a source of energy triggered that large-tremor warning, the USGS said it was "looking into it."

The earthquake had reportedly rumbled at approximately 9:48 a.m. Its epicenter is believed to be about 18 miles southwest of the island city of Avalon and 44 miles south of San Pedro, according to the United States Geological Survey. The earthquake struck at a depth of roughly 5 miles, USGS experts had said.

There were no reports of any damages or injuries.
https://www.msn.com/

Hi everyone - #ShakeAlert detected a non-earthquake event which triggered our system. Fortunately, no public alerts were sent out. This is a bit of a first time for us because these events happen so rarely. Apologies for any confusion from our previous tweets.

— USGS ShakeAlert (@USGS_ShakeAlert) April 15, 2022