- Its epicenter was near Cook Inlet
- "It was just soft at first, and it just kept getting bigger," Joshua Veldstra says
(CNN)A 7.1-magnitude earthquake struck Alaska early Sunday morning, according to the U.S. Geological Survey.
The quake's epicenter hit near Cook Inlet, 162 miles southwest of Anchorage. It was about 50 miles deep.
Joshua Veldstra, a professional photographer who lives in Homer, said the earthquake lasted about 30 seconds.
"When it hit, it was just soft at first, and it just kept getting bigger," Veldstra said. "It was one of those moments where you didn't' know if it was going to get worse or if it was going to calm down."
Anchorage police tweeted that there were no reports of major damage or injury following the earthquake.
The USGS reported that there was a low likelihood of casualties and damage, but the agency's "Did You Feel It?" map shows strong shaking could be felt near Anchorage.
The National Weather Service said there was no tsunami threat from the quake because of how deep it struck.
Two smaller earthquakes -- a 4.0 and a 3.2 -- struck within 30 minutes after the first one.