A  state of emergency had been declared across the Andean nation. Vice President Jorge Glas

" We have 16 people dead in the city of Portoviejo, 10 in Manta and two in the province of Guayas," in the west of the country. Police, the military and emergency services " are in a state of maximum alert." " There is considerable (structural) damage in the area near the epicenter as well as points as far away as Guayaquil," Ecuador' s Geophysical Office (IG) said.

Media published photographs of a bridge and the roof of a shopping center that collapsed in the port city of Guayaquil, Ecuador' s most populous city on the Pacific coast.

President Rafael Correa. " Authorities are already out evaluating damage and taking action" as needed," he said on Twitter that a national emergency committee had been activated.

- Tsunami warning - With a depth of 10 kilometers (six miles), the quake struck at 2358 GMT about 173 km west-northwest of Quito and just 28 kilometers south-southeast of Muisne, according to the US Geological Survey, which monitors earthquakes worldwide.

" Based on the preliminary earthquake parameters, hazardous tsunami waves are possible for coasts located within 300 kilometers of the earthquake epicenter," the Pacific Tsunami Warning Center said.

Buildings swayed in Quito but authorities did not immediately report injuries or damageThe strong movement was felt in northern and southern parts of the Quito area, knocking out electricity in places.

- Panic on the streets - Aftershocks kept rattling the country, as structural damage was reported in the coastal provinces of Manabi and Guayas. At the Guayaquil airport passengers awaiting flights dashed out of terminals when they felt the shaking.

" Lights fell down from the ceiling. People were running around in shock," said Luis Quimis, 30, who was waiting to catch a flight to Quito. In northern Quito, people ran out of their homes frightened, as power lines swayed back and forth and cables danced.

In fact, two earthquakes jolted the same area just 11 minutes apart, the USGS said. The first had a magnitude of 4.8 and the second of 7.8.

The quake also rattled northern Peru and southern Colombia, according to authorities in those countries, although no casualties were reported. Peruvian officials however urged coastal residents to stay away from the beach.

The quake came as rescuers in Japan were racing against the weather and the threat of more landslides to reach people still trapped by two big earthquakes that hit that country' s south.

At least 41 people are known to have died in that double disaster, with at least six still missing -- feared buried in shattered houses or under torrents of mud.

The Pacific Ring of Fire