PORTOVIEJO, Ecuador—Rescuers in Ecuador burrowed through deep rubble Sunday in an increasingly desperate attempt to find survivors of an earthquake that killed at least 246 people and allowed scores of inmates to escape prison.

READ: Ecuador’s biggest quake in decades kills over 240

About 2,500 people were injured when the strong 7.8-magnitude quake hit Saturday evening, Vice President Jorge Glas said, a sharp rise over the previous official figure of 1,557 hurt when buildings came crashing down.

Although the oil-producing South American nation frequently suffers seismic shudders because of its position on the so-called Ring of Fire that skirts much of the Pacific basin, the quake—though it lasted just one minute—was the worst in nearly 40 years in Ecuador.

The quake wrecked buildings, toppled power lines and sent terrified residents running from their homes when it struck a coastal zone popular with tourists.

Some 100 inmates in a prison in the western town of Portoviejo escaped when the quake shook their facility, Justice Minister Ledy Zuniga tweeted.

About 30 of them had been recaptured, some had returned voluntarily and police were hunting the others.

Elsewhere in hard-hit Portoviejo, rescuers raced to find survivors.

“We have already recovered three dead and we believe there are 10 to 11 people still trapped,” said one worker digging through the debris of what used to be a six-story hotel.

The smell of decaying bodies started to lace the tropical air.

Officials declared a state of emergency in the worst-hit provinces, and a national state of “exception,” both of which suspend certain civil rights and liberties to allow security forces and officials to react faster.

‘Lots of dead bodies’

Among the worst-hit towns was Pedernales, where Mayor Gabriel Alcivar estimated there were up to 400 more dead yet to be confirmed, many under the rubble of hotels that collapsed.

“Pedernales is devastated. Buildings have fallen down, especially hotels where there are lots of tourists staying. There are lots of dead bodies,” he told local media.

“We need help. We need medicine, water and food to help people.”

Ecuador‘s Geophysical Office reported “considerable” structural damage as far away as Guayaquil, Ecuador‘s biggest city with more than two million people, which is 350 kilometers (220 miles) away.

Two Canadians were among those killed by the quake, their country’s government told AFP.

In the town of Abdon Calderon, near Portoviejo, 73-year-old resident Nelly, who would not give her last name, told AFP in tears that she rushed into the street after the quake and saw that the covered market had collapsed.

“There was a person trapped who screamed for help, but then the screaming stopped. Oh, it was terrible,” she said.

Neighboring Colombia—which also felt the quake but emerged unscathed—and Mexico have dispatched aid and emergency workers to help in the rescue effort.

Some 200 aftershocks of lesser intensity have followed the quake.

Oil facilities undamaged

The epicenter of the quake was 170 kilometers northwest of the capital Quito, which suffered relatively little damage beyond cracks in walls and a power outage.

Officials said the oil infrastructure of Ecuador, an OPEC member, seemed intact.

Ecuador has suffered seven earthquakes of magnitude 7.0 or higher in the region of Saturday’s quake since 1900, the US Geological Survey said. One in March 1987 killed about 1,000 people.

David Rothery, a professor of geosciences at Britain’s Open University, said the 7.8 magnitude meant that “the total energy involved was probably about 20 times greater” than the magnitude 7.0 earthquake that killed at least 41 people in southern Japan on Saturday.

He said there was no causal link between the two quakes.

Pope’s prayers

President Rafael Correa, who was on a visit to the Vatican when the quake struck, called for “calm and unity” in a phone interview with Radio Publica.

Pope Francis urged prayers for the victims.

US Secretary of State John Kerry and EU chief diplomat Federica Mogherini expressed condolences and said they were ready to help.

The Red Cross said hundreds of its volunteers were joining in the search for survivors.

“In the coming days, we can expect acute health needs around trauma care and psychosocial support,” said Walter Cotte, of the International Federation of Red Cross and Red Crescent Societies. 

“There may also be urgent needs around maternal and obstetric care. We should also have to expect urgent needs around food, water, sanitation and shelter.”

Correa said on Twitter he would visit the stricken port city of Manta on Sunday evening.