An undersea volcano erupted dramatically near the peaceful nation of Tonga on Saturday, sending large tsunami waves crashing onto the shore and people rushing for higher ground. A tsunami advisory was in effect for Hawaii, Alaska and the U.S. Pacific Coast for much of the day, but was lifted for Oregon and Washington just before 5 p.m. Saturday.

The National Weather Service confirmed that the first large waves, more than a foot high, reached southern Oregon at 8:45 a.m. The agency encouraged people who live on boats in the bays and coastal ports to seek shelter and heights. After lifting the tsunami advisory, the agency noted that some areas along the coast could still experience strong currents and small changes in sea level.

A warning remained in effect from the Oregon-California border to the San Diego area, according to the US tsunami warning system.

In Hawaii, the Pacific Tsunami Warning Center reported waves crashing from one foot at Nawiliwili, Kauai, to 2.7 feet at Hanalei. “We are relieved that no damage was reported and only minor flooding across all islands,” the center said, describing the situation in Hawaii.

In Tonga, video posted on social media showed large waves washing up in coastal areas, swirling around houses and buildings.

The New Zealand military said it was monitoring the situation and remained on standby, ready to help if asked.

Satellite images showed a huge eruption, a plume of ash, steam and gas rising like a mushroom above the blue waters of the Pacific.

The Tonga Meteorological Service said a tsunami warning had been declared for the entire archipelago and data from the Pacific Tsunami Center showed waves of 80 centimeters (2.7 feet) had been detected.

In Hawaii, Alaska and along the U.S. Pacific Coast, residents were urged to move away from the coast to higher ground and heed specific instructions from their local emergency management officials, a said Dave Snider, tsunami warning coordinator for the National Tsunami Warning Center in Palmier, Alaska.

“We don’t issue reviews for this length of coast like we did – I don’t know when was the last time – but it’s really not an everyday experience,” he said. “I hope this elevates the significance and severity for our citizens.”

He said waves already slamming in Hawaii were just below criteria for a more severe tsunami warning, with readings at 80 centimeters (2.7 feet) at Hanalei and Maui. Waves of about 91 centimeters (3 feet) or more would trigger a warning. Snider said they currently expect waves of 30 centimeters (1 foot) to 61 centimeters (2 feet) along the Pacific coast.

Snider said residents of these areas should expect strong, unusual waves and currents for many hours and there could be flooded low-lying areas, such as marinas and ports.

“The important thing here is that the first wave may not be the most important. We could see this play out for several hours,” he added. “It looks like everything will remain below alert level, but that’s hard to predict because it’s a volcanic eruption and we’re set up to measure earthquakes or seismic sea waves.”

Residents of American Samoa were alerted to the tsunami warning by local broadcasters as well as church bells ringing across the territory. An outdoor siren warning system was out of order. Those who lived along the shore quickly moved to higher ground.

As night fell, no damage was reported and the Hawaii-based tsunami center canceled the alert.

Authorities in the neighboring island nations of Fiji and Samoa have also issued warnings, telling people to avoid the shore due to strong currents and dangerous waves. The Japan Meteorological Agency said there could be some slight water swelling along Japan’s coasts, but it shouldn’t cause any damage.

The Islands Business news site reported that a convoy of police and military evacuated King Tupou VI of Tonga from his palace near the shore. He was one of many residents heading for the higher ground.

The explosion of the Hunga Tonga Hunga Ha’apai volcano was the latest in a series of spectacular eruptions.

A Twitter user identified as Dr Faka’iloatonga Taumoefolau posted a video showing waves crashing on the shore.

“Can literally hear the eruption of the volcano, the sounds are quite violent,” he wrote, adding in a later post, “It’s raining ash and tiny pebbles, darkness covers the sky.”

Earlier, the Matangi Tonga news site reported that scientists observed massive explosions, thunder and lightning near the volcano after it erupted early Friday. Satellite images showed a plume 5 kilometers (3 miles) wide rising into the air about 20 kilometers (12 miles).

More than 2,300 kilometers (1,400 miles) away in New Zealand, authorities warned of storm surges from the eruption.

The National Emergency Management Agency said parts of New Zealand could expect “unusual strong currents and unpredictable surges on shore following a large volcanic eruption”.

The volcano is located about 64 kilometers (40 miles) north of the capital, Nuku’alofa. In late 2014 and early 2015, a series of eruptions in the area created a new small island and disrupted international air travel to the Pacific archipelago for several days.

Tonga is home to approximately 105,000 people.

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Associated Press writers Jennifer McDermott in Providence, Rhode Island, Mari Yamaguchi in Tokyo and Fili Sagapolutele in Pago Pago, American Samoa, contributed to this report.