CARACAS, Venezuela (AFP) — The United States (US) military raced to reopen a major port in Venezuela to ease aid deliveries on Monday as the deaths from last week’s twin earthquakes reached more than 1,700 with tens of thousands still reported missing.

Five days after powerful back-to-back quakes flattened entire neighbourhoods of multi-story buildings in the coastal state of La Guaira, hopes of finding survivors are fading.

At a makeshift morgue set up in a port warehouse in La Guaira, hundreds of bodies were stored in white and black body bags and coffins waiting to be identified, an AFP correspondent reported.

Dozens of relatives waited outside for news of their families as forensic personnel in blue uniforms examined the corpses.

“There were 11 people in my household; only two of us survived because we were at work,” Wilker Molalla told AFP.

“My family is there — I’m told my sister and her children are there, as well as the children of my brother.”

US Marines were meanwhile working to repair the quake-hit port to allow delivery of supplies and equipment, a US administration official told journalists in Washington.

American airmen were already helping to restore traffic at Simon Bolivar International Airport near Caracas, which was also damaged in one of the worst quake disasters in Latin American history.

The airport has already partially reopened to cargo and aid flights.

US helicopters have been ferrying in aid, and US Marines have used a landing craft to deliver supplies from the USS Fort Lauderdale, an amphibious transport dock ship docked at La Guaira.

The chances of finding anyone alive beneath meters deep of rubble have dwindled since the critical 72-hour window passed.

But a WhatsApp message ignited hopes of a miraculous find beneath the rubble, more than 120 hours after the disaster.

A woman wrote to the caretaker of a collapsed apartment building in Caraballeda, one of the worst-hit areas, about 40 kilometres from Caracas, to say she was still alive, volunteer rescuer Daniel Pino told AFP.

Also on Monday, a 21-year-old identified as Aaron Levi was rescued in the nearby town of Tanaguarena, according to a video released by a photographer who witnessed the complex operation to extract him.

Venezuelans are growing increasingly frustrated with what they see as the sluggish response of their US-backed government to the disaster.

Some 3,150 people were injured in Wednesday evening’s 7.2- and 7.5-magnitude quakes, which were also felt in neighbouring Colombia. They were Venezuela’s worst earthquakes in more than a century.

A strong aftershock Monday shortly after 7:00 am (1100 GMT) was measured by the US Geological Survey at magnitude 4.6, adding to fears for the safety of hundreds of buildings weakened by the tremors.

Twenty-four nations have sent 521 tons of supplies, including 86 units with dogs trained to locate people trapped beneath the rubble and more than 2,700 search-and-rescue personnel, according to interim president Delcy Rodriguez.

The United States, the main power broker in Venezuela since January when it overthrew longtime president Nicolas Maduro, on Monday doubled its previous aid pledge from $150 million to $300 million.

The few rescues have offered a glimmer of hope in a tragedy that has shaken a country mired in an economic crisis that has depleted its capacity to respond to disasters.

Some 774 buildings were badly damaged in the quakes, including 189 buildings that have totally collapsed, National Assembly President Jorge Rodriguez said on Sunday.

Luis Salas, 27, who joined the rescue efforts, told AFP that “the hardest part was when we felt hope in the tunnels we went into — crawling, clearing debris, working with all our heart, with great faith — and when we reached our targets, we found them lifeless.”

Even as rescue efforts continued, public anger has mounted in some areas.

Eduardo Cardozo, a volunteer in Tucacas, said it was “frustrating” to know that some victims could have been saved “if they’d been searched for in time.”

On Sunday, a group of residents ordered a group of soldiers to pick up picks and shovels and join in the rescue efforts.

“The country needs you. Put down your weapon,” one man ordered them.

Outbreaks of looting have hit La Guaira city, much of which now lies in rubble.

Pharmacies, supermarkets and other businesses were ransacked, said residents, some of whom complained of the slow and meagre post-quake aid coming from authorities.

Rodriguez has said temporary camps were being set up for people who had lost their homes.

The UN migration agency said that based on population and damage data, up to 6.76 million people could be affected, and would require shelter, water, sanitation, healthcare and essential relief items.