The National Weather Service shook the nerves of people on the Oregon Coast Wednesday – by accidentally issuing a tsunami warning.

The warning interrupted television and radio broadcasts in Portland, Eugene and along the coast.

The agency was testing its internal systems and didn’t mean for the bulletin to reach the public, said Tyree Wilde, the weather service’s warning coordination meteorologist in Portland.

“It was an inadvertent mistake we made,” he said.

The false alarm prompted residents to flood telephone lines at radio and television stations, the Oregon Emergency Management office and police and fire agencies.

Seaside’s Regional 9-1-1 Dispatch Center was inundated with calls for the first 20 minutes or so after the false warning was broadcast on local radio stations, said Seaside Police Lt. Dave Ham. He said calls continued sporadically throughout the day.

Seaside Police dispatcher Shelley Sakrisson added that in a real emergency, the police department would have received alerts from several other sources besides the NOAA weather radio.

Dick Lang, manager of Astoria’s 9-1-1 Dispatch Center, said about 20 calls came in soon after the warning went out over area radio stations and NOAA weather radio. There was one 9-1-1 call from a woman who was very panicked, Lang said. The rest of the calls were on the center’s non-emergency business line.

Lang said one person called from Lincoln City. When asked why, he said he had been getting conflicting information on TV, and “decided to call us because we would be hit first.”

Lang said the dispatch center does not depend on radio broadcasts for tsunami information.

“The NOAA weather radio is several tiers down from the information we rely on. We rely on the tsunami center in Palmer, Alaska. We’re confident we will receive the information if it’s forthcoming,” Lang said.

Elsewhere on the coast, the warning sparked fear and caused residents to act.

Hotels in Yachats began evacuation procedures before they learned that the warning was false.

Yachats fire chief Frankie Petrick said the phones rang off the hook all morning.

“They didn’t call 9-1-1,” she said. “They called me, to see if it was in fact a test and whether they should evacuate.”

This is the second warning in six months that didn’t produce a tsunami.

The last alert, June 14, resulted from a real earthquake off the coast of Crescent City, Calif. Thought the quake didn’t generate a tsunami, it created confusion and exposed gaps in preparedness at all levels of government and among the public.

Since then, emergency managers have been urging residents to head for high ground if they see or hear a tsunami warning.

“We’ve tried to tell people if you hear something, don’t call the radio stations, don’t call the TV, just go,” said Abby Kershaw, section director at Oregon Emergency Management. “If you’re going to tell people that, you can’t start putting a bunch of caveats on it. It’s definitely frustrating for us.”