A powerful magnitude-7.6 earthquake has shaken Costa Rica and neighbouring countries, sending panicked people into the streets and briefly triggering a tsunami alert, but causing little damage. 

Authorities reported one confirmed death.

The U.S. Geological Survey said the quake was centred about 60 kilometres from the town of Liberia. The magnitude initially was estimated at 7.9, but was quickly downgraded. Local residents said it shook for about 30 seconds.

While officials cancelled an initial tsunami warning, local police supervisor Jose Angel Gomez said about 5,000 people — 80 per cent of the population — had been evacuated from coastal towns in the Samara district west of the quake's centre several hours after the quake struck at 8:42 a.m. He said water was receding from the shore.

One man died of a heart attack caused by fright, said Carlos Miranda, a Red Cross worker in Liberia, but there were no reports of deaths directly caused by the quake.

Officials said the quake collapsed some houses and at least one bridge and caused landslides that blocked highways. But Costa Rica President Laura Chinchilla said there were no reports of major damage and called for calm.

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A magnitude-7.6 earthquake struck northwest Costa Rica on Wednesday morning, the U.S. Geological Survey said. (Google)

Douglas Salgado, a geographer with Costa Rica's National Commission of Risk Prevention and Emergency Attention, said a landslide hit the main highway that connects the capital to the Pacific coast city of Puntarenas, and hotels and other structures had cracked walls and items knocked from shelves.

"There's chaos in San Jose because it was a strong earthquake of long duration," Salgado said. "It was pretty strong and caused collective chaos."

The quake was also felt in neighbouring Nicaragua, which cancelled schools in some areas, and in Panama.

Residents, tourists shaken

Rosa Pichardo, 45, who lives in Samara, was walking on the beach with her family when the quake hit.

"When we felt the earthquake, we held onto each other because we kept falling," Pichardo said. "I've never felt anything like this. We just couldn't stay standing. My feet gave out under me. It was terrible, terrible."

In the town of Hojancha a few kilometres from the epicentre, city official Kenia Campos said the quake knocked down some houses and landslides blocked several roads.

"So far, we don't have victims," she said. "People were really scared … We have had moderate quakes but an earthquake (this strong) hadn't happened in more than 50 years."

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Patients at a hospital that was evacuated after a an earthquake struck Costa Rica on Wednesday morning. (Rodrigo Arangua/AFP/Getty Images)

Michelle Landwer, owner of the Belvedere Hotel in Samara, north of the epicentre, said she was having breakfast with about 10 people when the earthquake struck.

"The whole building was moving, I couldn't even walk," Landwer said. "Here in my building there was no real damage. Everything was falling, like glasses and everything."

In the coastal town of Nosara, roughly 30 kilometres southwest of the epicentre, trees shook violently and light posts swayed. Teachers chased primary school students outside as the quake hit. Roads cracked and power lines fell to the ground.

Reports of damaged buildings

Costa Rican television station Canal 13 reported that numerous homes, schools and a hospital on the peninsula were damaged, and it said the country's congress cancelled a session planned for later in the day.

Wednesday's quake occurred in a seismically active zone where the Pacific tectonic plate is diving beneath Central America.

"All along the Pacific coast of Central America, you can expect fairly big earthquakes," said seismologist Daniel McNamara of the U.S. Geological Survey.

'The whole building was moving, I couldn't even walk.' —Hotel owner Michelle Landwer

The quake was fairly deep — 41 kilometres below the surface. Deeper events tend to be less damaging than ones closer to the surface, but more widely felt.

"If it was a shallower event, it would be a significantly higher hazard," he said.

The last deadly quake to strike Costa Rica was in 2009, when 40 died in a magnitude-6.1 temblor. The last similar-sized quake to hit the country was in 1991 when 47 people were killed in the Limon-Pandora area.

While there was no immediate evidence of tsunami waves, a regional warning was issued based on the quake's strength.