(Corrects figure in 13th paragraph of Aug 18 story to say 200,000 people, not two million.)

KOCHI, India (Reuters) - India deployed thousands of soldiers and dozens of helicopters to rescue people marooned by the worst floods in a century in the southern state of Kerala, where the death toll of 186 people as of Saturday could rise fast as rains continue.

The weather office warned of more heavy “red” category rains on Saturday as tens of thousands of people were still stuck on the rooftops of houses and community centers. Rescue workers have yet to reach many flooded areas, some too narrow for boats to navigate.

People trapped without food, water and electricity worried about being left without help as their phone batteries were dying. An adviser to the state’s chief minister put the initial loss estimate at $4 billion.

(For a graphic on 'Kerala underwater' click, tmsnrt.rs/2L0MiIw)

“There are seven families in this apartment now. We’re safe compared to many others, but we’re cut off,” said James Joseph Moolakkaat, owner of an agricultural business who lives in a 10-story building across the southwestern state’s Periyar river.

“This is my second phone and to save power I have been turning data on and off intermittently. If this goes out, I will have some charge left in my laptop and then it will be incommunicado.”

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Prime Minister Narendra Modi, who was taken by helicopter over inundated farmland and villages, promised more helicopters, boats and other equipment needed to expand the rescue operation in the still unfolding emergency.

He said the Army, Air Force, Navy and Coast Guard were assisting disaster relief agencies in the rescue, and a total of 38 helicopters had been pressed into service along with a number of aircraft and ships to ferry resources.

“More helicopters, boats and other equipment are being sought and Modi promised to provide all of these as fast as possible,” Kerala Chief Minister Pinarayi Vijayan told journalists. “The air marshal in charge of the air operations said more helicopters are on the way.”

According to a lawmaker in Pathanamthitta district, some 10,000 people were stranded and in grave danger unless they were rescued urgently.

A Reuters witness in Aluva town, nearly 250 km (155 miles)from state capital Thiruvananthapuram, said army helicopters airlifted up to 14 marooned residents, including children and elderly people from an apartment.

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FOOD SHORTAGES

With hundreds of thousands of people converging in halls and auditoriums of schools, temples, churches, and mosques with little or no toilet facilities, people from less affected areas moved in to help those badly in need.

But some people in the relief camps were finding it difficult to access food and water. Videos on social media showed groups of people breaking open shops to take food.

Chief Minister Vijayan has estimated that more than 200,000 people have been forced to move into relief camps since the monsoon season brought torrential rains three months ago. He put the death toll from floods and landslides since the start of the rainy season at 324.

One of his advisers, Prabha Varma, told Reuters 186 people had died since Aug. 8, when the waters began to rise. He said the floods had destroyed 26,000 homes and damaged crops across as much as 40,000 hectares, with estimated losses of 277 billion rupees.

Modi declared initial assistance of 5 billion rupees ($71 million) and promised more later. He also assured that the federal government would send desperately needed grains, as storage in the state had been flooded and stocks destroyed.

Sheikh Mohammed bin Rashid Al Maktoum of the United Arab Emirates, where many Keralites work, said he had formed a committee to extend emergency assistance to the flood victims of the state, whose people he said “have always been and are still part of our success story”.