Rain and wind lashed India's east coast forcing about 450,000 people to flee to shelters as one of the country's largest cyclones closed in, threatening to cut a swathe of devastation through farmland and fishing hamlets.
The storm was expected to affect 12 million people, most of them in the densely populated states of Odisha and Andhra Pradesh, weather and disaster management officials said.
Filling most of the Bay of Bengal, Cyclone Phailin is expected to strike the coast by nightfall with winds of between 210 kph (130 mph) and 220 kph (137 mph).
Phailin is expected to bring a 3.4-m (11-foot) surge in sea levels when it hits the coast.
London-based Tropical Storm Risk said the storm was already the "super cyclone" category, and classed it as a Category 5 storm - the strongest. The US Navy's weather service said wind at sea was gusting at 314 kph.
Some forecasters likened its size and intensity to hurricane Katrina, which tore through the US Gulf coast and New Orleans in 2005. Its scale also stirred memories of a 1999 Indian storm when winds reaching speeds of 300 kph battered Odisha for 30 hours.
Families walked through the rain to shelters, television images showed, as gusts of wind snapped branches from trees.
"The storm has high damage potential, considering windspeed," Lakshman Singh Rathore, head of the weather department, said.
Tourists left popular beach resort Puri. Officials broadcast cyclone warnings through loudspeakers, radio and television.
– East coast state Odisha's Special Relief Commissioner, Pradeep Kumar Mohapatra.
The wind speed is picking up.
Some people were earlier reluctant to move. They are willing now.
Filling most of the Bay of Bengal, Phailin was about 300 km offshore on Saturday morning, satellite images showed, and was expected to reach land by nightfall. Officials said the storm was verging on becoming a "super cyclone."
Rain and wind lashed India's east coast and nearly 400,000 people fled to cyclone shelters after the government issued a red alert and warned of severe damage when one of the largest storms the country has ever seen makes landfall later on Saturday.
Muslims and Hindus gathered at mosques and temples in Odisha state, praying Cyclone Phailin would not be as devastating as a similar storm that killed 10,000 people 14 years ago. Heavy rain pounded coastal villages in neighboring Andhra Pradesh.
Phailin was packing winds of at least 220 kph (137 mph) on Saturday morning and was expected to cause a 3.4-m (11-foot) surge in sea levels when it hits the coast in the evening, the India Meteorological Department said in a statement.
The Foreign and Commonwealth Office has advised against all travel in the immediate vicinity of the border with Pakistan, other than at Wagah.
The FCO has also advised against all travel to Manipur and all but essential travel to Imphal, the state capital of Manipur.
It advises against all travel to Jammu and Kashmir with the exception of the cities of Jammu and Srinagar, travel by air to the cities of Jammu and Srinagar, travel between these two cities on the Jammu-Srinagar national highway and travel within the region of Ladakh.
The FCO also advises against travel to Jammu and Kashmir with the exception of the cities of Jammu and Srinagar, travel by air to the cities of Jammu and Srinagar, travel between these two cities on the Jammu-Srinagar national highway and travel within the region of Ladakh.
A quarter of a million people have fled their homes in eastern India as the fiercest storm for more than a decade is set to hit.
The cyclone, carrying winds of more than 130mph, could make landfall within the next day.
ITV News Correspondent Harry Smith reports:
Huge crashing waves along the south Indian shoreline have heralded the impending arrival of the fiercest cyclone in more than a decade.
Tens of thousands have fled their homes in coastal areas and moved to shelters.
Tens of thousands of residents in low-lying areas of India have begun fleeing their homes as a giant cyclone approaches the country's east coast.
Satellite images showed Cyclone Phailin 600 km (360 miles) off the coast in the Bay of Bengal and likely to make landfall on Saturday evening.
Some forecasters likened its size and intensity to that of hurricane Katrina, which devastated the US Gulf coast and New Orleans in 2005.
Satellite images showed the storm covering an area roughly half the size of India.
The Indian Meteorological Department described Phailin as a "very severe cyclonic storm" with wind speeds of 210-220 km per hour (130-135 mph).