The 7.0 magnitude earthquake struck just south of Point MacKenzie, Alaska, with an epicenter seven miles (11.4 km) from Anchorage, the U.S. Geological Survey said. It had a depth of 26.7 miles (43 km).
The National Weather Service initially said there was no tsunami danger, but a few minutes later the agency said on Twitter that there was a warning in place for Cook Inlet, which links Anchorage with the Gulf of Alaska.
The quake was initially reported as having a 6.7 magnitude.