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QUITO, April 17 (Xinhua) -- The strongest earthquake to jolt Ecuador in decades has killed 235 people, as rescuers raced to dig out survivors trapped in the rubble.

Residents stand in front of the debris of houses after an earthquake in the city of Chone, Manabi Province, Ecuador, on April 17, 2016. The strongest earthquake to jolt Ecuador in decades has killed 233 people, the country's President Rafael Correa said on Sunday, as rescuers raced to dig out survivors trapped in the rubble. (Xinhua/Jorge Penafiel/EL UNIVERSO)

The official death toll from Saturday's devastating 7.8-magnitude earthquake has risen to 235 dead and 1,557 injured, Vice President Jorge Glas, visiting the quake zone, said on Sunday.

At a press conference broadcast live on television, Glas said the priority was to continue searching for survivors in the rubble and to help the injured.

The earthquake struck at 18:58 local time Saturday (2358 GMT) with its epicenter at a depth of 10 kilometers located in northwest of Ecuador's coast. The temblor so far has generated at least 189 aftershocks of various strength.

The quake, felt around the Andean nation of 16 million people, cracked highways and collapsed buildings in a swath of western towns, causing panic as far away as in the capital city of Quito when buildings were swayed.

Ecuador has declared a state of emergency in six provinces and has mobilized around 14,000 army and public security personnel to affected areas.

"We will overcome this. I send a message of calm and my deep solidarity to those who lost their relatives," said Glas, who is in charge of coordinating emergency response.

Glas visited the affected cities of Manta and Portoviejo in the northeastern province of Manabi, the hardest-hit and difficult to reach due to damaged highways.

"We are facing logistical difficulties," said Glas, noting that specialized rescue teams have reached the worst-hit zones, with technologies and supplies.

Besides Manabi, the provinces of Esmeraldas, Guayas, Los Rios, Santa Elena and Santo Domingo de los Tsachilas have declared emergencies.

The vice president said international humanitarian aid would begin arriving Sunday and called on people to refrain from rescuing their belongings from the rubble.

There was no risk of a tsunami and the water reservoirs in Manabi had not been affected, he added.

"Through calm, strength and faith, we will overcome this challenge from nature," said Glas, who was set to travel by helicopter to Pedernales, a popular tourist spot town of 40,000 near the quake's epicenter.

President Rafael Correa was rushing back home from Italy. He wrote on Twitter earlier on the day that he planned to visit the hard-hit city of Manta on Sunday night.

The government has tapped up to 300 million U.S. dollars for rescue and rebuilding efforts.

Saturday's earthquake was the strongest to hit Ecuador since 1979. Ecuador is located in a region with frequent volcanic eruptions and earthquakes.