Governments worldwide scrambled Thursday to get their nationals out of the chaos of Libya, as Italy warned of a "biblical" exodus of up to 300,000 migrants and anger built among trapped foreigners.

Fears of a full-scale civil war in the North African country prompted countries from Canada to China to charter ferries and planes to get their citizens to safety despite poor communication and violent clashes.

Thousands of foreigners packed Tripoli's airport hoping to leave the widening chaos behind, with those who managed to flee describing anarchic scenes with food and water supplies running low.

As Libya's defiant leader Moammar Gaddafi clung to power, China ramped up a massive air, sea and land operation to evacuate more than 30,000 of its citizens, with over 4,000 transferred to the Greek island of Crete Thursday.

Thailand, which has more than 23,000 workers in Libya, said it was making preparations to get its citizens to Malta, but warned it may be safer for them to stay in their compounds than to travel to a port.

"I have received information that the route is dangerous due to looting," said Prime Minister Abhisit Vejjajiva. "They are safe in their camps now."

Hundreds of American nationals and other foreigners have boarded a US-chartered ferry in Tripoli but high seas delayed their departure for Malta.

Turkey evacuated upwards of 6,000 of its nationals over three days by air, sea and land in a massive operation, but thousands were still waiting to leave with an estimated 25,000 Turks based in Libya.

The logistical challenges were especially acute for Asian countries with over 150,000 low-paid workers trapped - including some 60,000 Bangladeshis and 30,000 Filipinos.

Migrante International, a support group for overseas Philippines workers, said Filipinos had been left to fend for themselves, as Vice President Jejomar Binay planned to fly to the region to review emergency plans.

Migrante chairman Gary Martinez complained that the government had "really messed up".

"When we spoke to one group of construction workers last night, they said they will try to make it across the border to Egypt by bus today (Thursday), because they haven't heard from any government official," he said.

India said a 1,000-capacity passenger ship had arrived on the Libyan coast to begin evacuating some of its 18,000 nationals to Egypt, adding that the operation had been hampered by poor communications.

An official at the Vietnamese embassy said it was trying to get its 10,000 nationals out, but warned that they were short of food and water.

A flight from Tripoli with 150 stranded oil workers arrived in London. Britain's government rebuffed criticisms over its rescue mission, saying it would send as many flights as necessary, possibly including military planes.

Oil worker James Coyle told BBC radio he was one of 90 Britons trapped in a desert camp among 300 people, including Pakistanis, Bangladeshis, Germans, Austrians and Romanians.

"We are living a nightmare and we have asked the British government and they have just totally ignored us," he said.

"They don't reply to emails, they have cut off the phones to Tripoli. We told them the situation three days ago - they never even replied to us."

Brazil, Canada and South Korea were among other countries striving to get their nationals out by ship or plane.

The EU's executive arm said it would provide "extra evacuation capacity" including by sea to help bring out an estimated 10,000 stranded Europeans. Two planes carrying around 500 French nationals arrived in Paris early Wednesday while more than 300 Russian railroad and oil workers and their families returned to Moscow aboard three planes.

"They burned down a police station next to our house. There is a lot of gunfire at night - rounds of machine-gun fire. We spent sleepless nights," one woman told Russian state television on arrival.

Already grappling with a mass influx of immigrants from Tunisia since the fall of its veteran ruler, Italy warned that the exodus from Libya could be far larger.

"We know what awaits us when the Libyan regime falls: a wave of 200-300,000 immigrants," Foreign Minister Franco Frattini said.