The death toll from twin earthquakes rose to 1000 in Venezuela, where tens of thousands were reported missing as a desperate and slow-moving search for survivors was boosted by international rescue teams.

Caracas residents jeered interim leader Delcy Rodriguez during her visit to a devastated neighborhood, as fury over the perceived lack of an official response mounted.

United Nations aid chief Tom Fletcher told AFP that more than 50,000 people were missing after two powerful earthquakes struck within a minute of each other on Wednesday evening, flattening buildings in the north of the country.

The coastal area of La Guaira, near the capital Caracas, was the worst hit, with one building after another crumpled by the magnitude 7.2 and 7.5 quakes.

Access to the disaster zone would be restricted from 8:00 pm local time (0000 GMT) on Friday, Interior Minister Diosdado Cabello announced in a televised address.

A rescue team from Chile arrived at one residential complex in La Guaira, made up of four tall buildings housing hundreds of apartments that had largely been reduced to rubble.

"Unfortunately, the collapse is total, and there is little chance of finding survivors. Efforts are now focused on recovering the bodies of the deceased," rescue team leader Nadiomar Polanco said at the site, which resembles many others in the city.

Elsewhere, family members, neighbors and volunteers used their bare hands to try to dig out survivors, bemoaning the lack of heavy machinery or official help to save those trapped alive.

"I am looking for my little Gael... he was only five months old," said an anguished Marjosly Salazar, 40, whose 16-year-old daughter died in the quake. The baby and Salazar's cousin are both missing.

"Please, we need support here. We need machinery to start lifting the columns," she said. "We haven't seen any government officials here, none at all."

In an upscale Caracas neighborhood, Rodriguez was greeted with angry chants from a crowd of people whose loved ones were trapped under the debris.

"The government isn't doing anything for the people," they yelled from behind cordons next to a pulverized building.

Sun News/ra