The 7.0 magnitude quake struck about 13 km north of Anchorage, a city of 300,000 residents.
A powerful earthquake jolted southern Alaska on Friday morning, buckling roads, disrupting rush-hour traffic and jamming telephone service in and around Anchorage, the state's largest city, but there were no reports of serious injuries.
The 7.0 magnitude quake struck about 13 km north of Anchorage, a city of 300,000 residents accounting for about 40 percent of Alaska's population, and was followed by dozens of aftershocks that continued to rattle nerves throughout the day.
Public schools and many businesses across Anchorage closed early, and an eerie quiet settled over the city's largely deserted streets by nightfall. At least two local television stations were briefly knocked off the air by the tremor, which some people said sounded like a roar of gunfire.
Roads and bridges appeared to have been hardest hit, but Anchorage was otherwise mostly spared from major structural damage, authorities said. Power outages and disruption of phone service were widespread.
City Fire Chief Jodie Hettrick said two small, older buildings had collapsed, and that her department responded to several structure fires.