COLOMBO, Sri Lanka -- Helicopters searched for people marooned four days after rain-triggered floods and mudslides inundated Sri Lankan neighborhoods and killed at least 169 people.

With more rain expected Monday, rescuers raced to evacuate people from the most vulnerable areas. Already more than 100,000 have taken shelter in 339 relief camps set up in the south and west.

Army boats skimmed waterlogged village streets, while able-bodied flood victims waded through brackish waters to army trucks carrying relief supplies.

Sri Lankan army soldiers walk past the debris of houses at a landslide site during a rescue mission in Athwelthota village, in Kalutara, Sri Lanka May 28, 2017. Dinuka Liyanawatte

An air force helicopter on relief mission crash landed near Baddegama town in southern Sri Lanka on Monday. All 11 people onboard escaped unhurt. Earlier an airman died after a fall while trying to rescue a marooned person from the air.

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"We are displaced and have no place to go," said Rathana Kumari, who fled her flooded home with her family and took refuge on the Southern Expressway, a major highway linking the commercial capital of Colombo with the cities of Matara and Galle. "Now we are extremely helpless with our little children. ... Today, we didn't get anything to eat."

Officials say at least 102 people are still missing since the floods hit on Friday along with cascades of red mud that swallowed village homes.

People travel on top of an armoured personnel carrier on a flooded road as a jeep drives thorugh the water in Bulathsinhala village in Kalutara, Sri Lanka May 27, 2017. Dinuka Liyanawatte

Special medical teams have been sent to the affected areas, while medicine has been sent by air to hospitals unreachable by road, said Health Minister Dr. Rajitha Senarathna.

Soldiers took advantage of a lull in the rain Sunday to clear roads to reach some affected areas, said Maj. Gen. Sudantha Ranasinghe, who is heading the search and rescue mission.

The United Nations said it had joined the relief efforts and would donate water purification tablets, tents and other supplies for the displaced. India sent two shiploads of goods and some medical staff while the United States and Pakistan also promised relief supplies.

Mudslides have become common during Sri Lanka's summer monsoons, as forests across the tropical Indian Ocean island nation are cleared for export crops such as tea and rubber.

Another massive landslide a year ago killed more than 100 people in central Sri Lanka.