San Francisco Frontiers - Dozens of international teams rushing to Venezuela: UN

Getting those search and rescue teams to the scene is the "top priority", the UN humanitarian agency OCHA said.

"Earthquakes are one of the most devastating things that can happen to any country," spokesman Jens Laerke told reporters in Geneva. "It really is a terrifying thing.

"But what we are seeing right now is also an international mobilisation at its very best.

"The entire humanitarian system is moving very fast, and at scale."

A total of 25 teams -- 17 national urban search and rescue teams, with the rest emergency medical response teams -- were being deployed, with a total of 1,000 rescue personnel, he said. And there was more to come.

Teams from Chile, Colombia, El Salvador, Italy, Mexico, Switzerland and the United States were already in Venezuela, said Laerke.

Teams from Britain, the Czech Republic, Ecuador, France, Germany, Jordan, the Netherlands, Qatar and Spain among others are also being mobilised.

The 7.5- and 7.2-magnitude earthquakes on Wednesday are known to have killed at least 235 people.

- Rescue still priority -

The World Health Organization said the immediate needs included mass casualty management and trauma care, particularly in areas with collapsed buildings.

"The overriding priority is to rescue as many people as possible while urgently providing life-saving health care to the injured," said Ciro Ugarte, emergencies director for PAHO, the UN health agency's Americas regional branch.

"The first 72 hours are critical to saving lives, and efforts are heavily focused on ensuring timely medical attention for those affected," he said, speaking from Washington.

"The number of deaths and injured people will significantly increase in the coming hours and days."

He said the earthquakes had hit a health system that was already fragile, but more than 15 health ministries in the region had pledged support and were ready to deploy teams.

Ugarte said PAHO experts were working on mapping the affected health facilities. They had identified more than 90 hospitals exposed to shaking intensities beyond six and seven on the Modified Mercalli intensity scale.

"We are prioritising those facilities, including the assessment of the structural safety, emergency department capacities, operating theatres, inpatient beds, blood supply, and oxygen," he said.

"Hospitals are managing injuries such as broken bones and head injuries, but also we are seeing burns and other injuries that result from building collapse," he added.

H.Davis--SFF