The 'golden window' to reach survivors of Venezuela's twin earthquakes ran out last night, with rescuers fearing tens of thousands are dead under the rubble.

Nearly 1,500 people are confirmed dead – but at least 50,000 are missing after back-to-back earthquakes struck the South American country on Wednesday evening.

Rescuers continued to pull people from the rubble yesterday – including a newborn baby, which survived.

But one rescuer told CNN: 'The clock is running out. We consider the first 48 to 72 hours after a quake as the golden window to reach people buried alive under the rubble.

'After that the chances of survival without water diminishes rapidly.'

A 68-strong UK International Search and Rescue team flew from RAF Brize Norton on Friday, joining more than 2,000 others from around the world in the search for survivors.

Two powerful quakes rocked the country shortly after 6pm Wednesday within seconds of each other.

The first was a magnitude 7.2 followed 36 seconds later by a magnitude 7.5 quake, the strongest to hit Venezuela in a century.

Horrific images have emerged of collapsed shopping centers and residential tower blocks with local hospitals saying they are 'overwhelmed' with the injured.

The coastal community of La Guaira, north of the capital Caracas, was hardest hit with 'tens of thousands' feared dead amid ongoing aftershocks.

At least 1,600 buildings in Caracas were flattened.

Residents said buildings and infrastructure like bridges and roads collapsed within seconds.

Survivor Graciela Mora said: 'My friend standing beside me was killed when part of our building collapsed. It happened within seconds. I held onto the doorframe with everything I had. I broke my fingers but stayed alive.'

Benito Quivera from Caracas said rescue teams were 'digging with their bare hands' because the country has little heavy rescue equipment.

Hector Bellow, a defender for La Guaira's football team, said his wife Andrea, 26, was killed as she shielded their one-year-old daughter Alana from falling debris.

He wrote on social media: 'I'll tell her the story of how you saved her, how you gave your own life for our daughter, how you were a brave woman who, even with your last breaths, never abandoned her.'

Venezuela has been in turmoil since President Trump seized socialist leader Nicolas Maduro in a nighttime raid in January.

He remains in New York awaiting trial on terrorism and drugs charges.

Trump has sent US rescue teams and $150 million in aid to the country saying 'America stands ready, willing and able to help' calling the people 'our new and great friends.'

The US Geological Survey has estimated the final death toll could range from 10,000 to 100,000.

A spokesperson for Acting President Delcy Rodriguez said: 'We are in a race against time to find survivors. There are still 50,000 unaccounted for. Keep Venezuela in your prayers.'

Oil-rich Venezuela, a country of 28 million, was once one of the most prosperous nations in Latin America but has suffered decades of economic decline and political unrest.