This aerial photo shows damage on Vine Road, south of Wasilla, Alaska, after earthquakes Friday, Nov. 30, 2018. Back-to-back earthquakes measuring 7.0 and 5.7 shattered highways and rocked buildings Friday in Anchorage and the surrounding area, sending people running into the streets and briefly triggering a tsunami warning for islands and coastal areas south of the city. (Marc Lester/Anchorage Daily News via AP)

Chris Riekena was driving his 7-year-old son to school when his car started acting up. As he pulled over, he realized the problem wasn't his car—it was a huge earthquake.

Riekena turned around to calm his son in the back seat and when he looked forward again, the road ahead of him was sinking into the earth. He pulled his son out of the car as light poles along the road swayed in the air.

By the time the shaking stopped Friday, the car just in front of his on the freeway was marooned on an island of asphalt with a huge chasm on both sides.

"It was probably a good 30 to 40 seconds of slow-motion disaster," said Riekena, an engineer with the Alaska Department of Transportation who later returned to the site for his job.

"Thankfully I pulled over when I did," he said. "I've walked around the site enough over the last few hours that I've replayed that a few times."

Back-to-back earthquakes measuring 7.0 and 5.7 shattered highways and rocked buildings Friday in Anchorage and the surrounding area, sending people running into the streets and briefly triggering a tsunami warning for islands and coastal areas south of the city.

No tsunami arrived and there were no reports of deaths or serious injuries.

An employee walks past a damaged aisle at Anchorage True Value hardware store after an earthquake, Friday morning, Nov. 30, 2018, in Anchorage, Alaska. Tim Craig, owner of the south Anchorage store, said no one was injured but hundreds of items hit the floor and two shelves collapsed in a stock room. (AP Photo/Dan Joling)

The U.S. Geological Survey said the first and more powerful quake was centered about 7 miles (12 kilometers) north of Anchorage, Alaska's largest city, with a population of about 300,000. People ran from their offices or took cover under desks. The 5.7 aftershock arrived within minutes, followed by a series of smaller quakes.

"We just hung onto each other. You couldn't even stand," said Sheila Bailey, who was working at a high school cafeteria in Palmer, about 45 miles from Anchorage, when the quake struck. "It sounded and felt like the school was breaking apart."

Anchorage Police Chief Justin Doll said he had been told that parts of Glenn Highway, a scenic route that runs northeast out of the city past farms, mountains and glaciers, had "completely disappeared."

The quake broke store windows, knocked items off shelves, opened cracks in a two-story building downtown, disrupted electrical service and disabled traffic lights, snarling traffic.

Flights at the airport were suspended for hours after the quake knocked out telephones and forced the evacuation of the control tower. And the 800-mile Alaska oil pipeline was shut down for hours while crews were sent to inspect it for damage.

A car is trapped on a collapsed section of the offramp of Minnesota Drive in Anchorage, Friday, Nov. 30, 2018. Back-to-back earthquakes measuring 7.0 and 5.8 rocked buildings and buckled roads Friday morning in Anchorage, prompting people to run from their offices or seek shelter under office desks, while a tsunami warning had some seeking higher ground. (AP Photo/Dan Joling)

Anchorage's school system canceled classes and asked parents to pick up their children while it examined buildings for gas leaks or other damage.

Jonathan Lettow was waiting with his 5-year-old daughter and other children for a school bus near their home in Wasilla, about 40 miles north of Anchorage, when the quake struck. The children got on the ground in a circle while Lettow tried to keep them calm and watched for falling trees.

"It's one of those things where in your head, you think, 'OK, it's going to stop,' and you say that to yourself so many times in your head that finally you think, 'OK, maybe this isn't going to stop,'" he said.

Soon after the shaking ended, the school bus pulled up and the children boarded, but the driver stopped at a bridge and refused to go across because of deep cracks in the road, he said.

Gov. Bill Walker issued a disaster declaration. He was in an elevator in a high-rise Anchorage office building and said it was a "rough ride" coming down. He described the quake as a 7.2, though it was unclear why his figure differed from that of the USGS.

A ramp from International Airport Road to Minnesota Drive was damaged in an earthquake on Friday, Nov. 30, 2018, in Anchorage, Alaska. Alaska Gov. Bill Walker says it will take more than a week or two to repair roads damaged by the powerful earthquake. (Marc Lester/Anchorage Daily News via AP)

Walker says it will take more than a week or two to repair roads damaged by the earthquake.

"This is much more significant than that," he told reporters at a news conference.

In Kenai, southwest of Anchorage, Brandon Slaton was soaking in his bathtub when the earthquake struck. The temblor created a powerful back-and-forth sloshing that threw him out of the tub, he said.

His 120-pound mastiff panicked and tried to run down the stairs, but the house was swaying so much that the dog was thrown into a wall and tumbled down the stairs, Slaton said.

Slaton ran into his son's room after the shaking stopped. The boy's fish was on the floor, gasping, its tank shattered. Slaton put the fish in a bowl.

This aerial photo shows damage at the Glenn Highway near Mirror Lake after earthquakes in the Anchorage area, Alaska, Friday, Nov. 30, 2018. Back-to-back earthquakes measuring 7.0 and 5.7 shattered highways and rocked buildings Friday in Anchorage and the surrounding area, sending people running into the streets and briefly triggering a tsunami warning for islands and coastal areas south of the city. (Marc Lester/Anchorage Daily News via AP)

"It was anarchy," he said. "There's no pictures left on the walls, there's no power, there's no fish tank left. Everything that's not tied down is broke."

Alaska was the site of the most powerful earthquake ever recorded in the U.S. The 9.2-magnitude quake on March 27, 1964, was centered about 75 miles (120 kilometers) east of Anchorage. It and the tsunami it triggered claimed about 130 lives.

The state averages 40,000 earthquakes a year, with more large quakes than the 49 other states combined. Southern Alaska has a high risk of earthquakes because the Earth's plates slide past each other under the region.

Alaska has been hit by a number of powerful quakes over 7.0 in recent decades, including a 7.9 last January southeast of Kodiak Island. But it is rare for a quake this big to strike so close to such a heavily populated area.

David Harper was getting coffee at a store when the low rumble began and intensified into something that sounded "like the building was just going to fall apart." He ran for the exit with other patrons.

"People who were outside were actively hugging each other," he said. "You could tell that it was a bad one."

Merchandise fell from shelves and racks at Andy's Ace Hardware on Muldoon Road after the Friday, Nov. 30, 2018, earthquake hit Southcentral Alaska. Scientists say the damaging Alaska earthquake and aftershocks occurred on a type of fault in which one side moves down and away from the other side. (Bill Roth/Anchorage Daily News via AP)

In this photo provided by Jonathan M. Lettow, people walk along Vine Road after an earthquake, Friday morning, Nov. 30, 2018, in Wasilla, Alaska. (Jonathan M. Lettow via AP)

Traffic outbound from Anchorage on the Glenn Highway was at a standstill after a 7.0-magnitude earthquake caused damage in the Anchorage, Alaska, on Friday, Nov. 30, 2018. Scientists say the damaging Alaska earthquake and aftershocks occurred on a type of fault in which one side moves down and away from the other side. (Marc Lester/Anchorage Daily News via AP)

Randy Van Ness mops an aisle at Andy's Ace Hardware after a 7.0-magnitude earthquake hit in Anchorage, Alaska, Friday, Nov. 30, 2018. Scientists say the damaging Alaska earthquake and aftershocks occurred on a type of fault in which one side moves down and away from the other side. (Bill Roth/Anchorage Daily News via AP)

This aerial photo shows a landslide on the northwest side of Knik Arm after earthquakes in the Anchorage area, Alaska, Friday, Nov. 30, 2018. Back-to-back earthquakes measuring 7.0 and 5.7 shattered highways and rocked buildings Friday in Anchorage and the surrounding area, sending people running into the streets and briefly triggering a tsunami warning for islands and coastal areas south of the city. (Marc Lester/Anchorage Daily News via AP)

Snow slid from the bluff at Point Woronzof, near Ted Stevens Anchorage International Airport when a 7.0-magnitude earthquake caused damage in the Anchorage, Alaska, on Friday, Nov. 30, 2018. Scientists say the damaging Alaska earthquake and aftershocks occurred on a type of fault in which one side moves down and away from the other side. (Marc Lester/Anchorage Daily News via AP)

This aerial photo shows damage on Vine Road, south of Wasilla, Alaska, after earthquakes Friday, Nov. 30, 2018. Back-to-back earthquakes measuring 7.0 and 5.7 shattered highways and rocked buildings Friday in Anchorage and the surrounding area, sending people running into the streets and briefly triggering a tsunami warning for islands and coastal areas south of the city. (Marc Lester/Anchorage Daily News via AP)

Damage from an earthquake is seen on the Glenn Highway southbound lanes between Eklutna and Mirror Lake, in Alaska, Friday, Nov. 30, 2018. A 7.0 magnitude temblor hit on Friday morning. DOT project engineer Rod Cummings said the inbound lanes of the highway will be closed for several days, but the highway is open and inbound traffic will be routed around the area until crews can repair the damage. (Matt Tunseth/Anchorage Daily News via AP)

Marty Thurman with Granite construction inspects a crack in the road at the International Airport Road offramp on southbound Minnesota Blvd., in Anchorage, Alaska, Friday, Nov. 30, 2018. A state official says Ted Stevens Anchorage International Airport is open and operating at reduced capacity with delayed flights following back-to-back earthquakes. (Loren Holmes/Anchorage Daily News via AP)

Cases of beer lie jumbled in a walk-in cooler at a liquor store, Value Liquor, after an earthquake on Friday, Nov. 30, 2018, in Anchorage, Alaska. Owner Mary Funner says beer, wine and other bottled alcohol was strewn throughout store aisles after the quake. She considered closing Friday until customers began lining up. They were allowed to come in in small groups. "We're still in business, but we're only open only a little bit at a time," she said. (AP Photo/Dan Joling)

Dennis Keeling, of Instant Services, measures for a broken window at an auto parts store following an earthquake Friday, Nov. 30, 2018, in Anchorage, Alaska (AP Photo/Mike Dinneen)

Workers inspect an off-ramp that collapsed during a morning earthquake, Friday, Nov. 30, 2018, in Anchorage, Alaska. (AP Photo/Mike Dinneen)

In this photo provided by Jonathan M. Lettow, people walk along Vine Road after an earthquake, Friday, Nov. 30, 2018, in Wasilla, Alaska. (Jonathan M. Lettow via AP)

In this photo provided by Jonathan M. Lettow, people walk along Vine Road after an earthquake, Friday, Nov. 30, 2018, in Wasilla, Alaska. (Jonathan M. Lettow via AP)

Explore further Strong earthquake rattles remote Alaska region

© 2018 The Associated Press. All rights reserved.