Back-to-back quakes shake Alaska

Two earthquakes jolted Anchorage, Alaska, making buildings shudder and knocking items off shelves.

There are no immediate reports of serious damage or injuries.

The Alaska Tsunami Warning Center says the quakes had a preliminary magnitude of 4.8 richter scale.

"We're thinking it might be bigger, but that's the magnitude we're going with initially," the center's Bruce Turner said. Palmer is about 40 miles northeast of Anchorage.

Marlene Lammers of the Anchorage Police Department said the department had received no reports of damage. Storekeepers and some residents said some things had fallen off shelves.

The quakes were not strong enough to generate a tsunami, a damaging seismic sea wave, the warning center said.