Cyclone Phailin left a trail of destruction along India's east coast and at least seven people dead Sunday, after the biggest evacuation in the country's history helped minimise casualties.

As emergency teams began assessing damage from the country's biggest cyclone in 14 years, a massive relief effort went into full swing to distribute food to an estimated one million evacuees, clear roads and help the injured.

Most of the local population spent the night huddled in shelters and public buildings as deafening winds flattened flimsy homes, uprooted trees, and sent glass and asbestos strips flying through the air.

The worst affected area, around the town of Gopalpur in Orissa where the eye of Phailin came ashore packing winds of 200 kilometres an hour (125 miles per hour), was still without power and communications were down.

Roads strewn with fallen trees were at least open, as emergency services rushed to reach people living there.

Raj Kishor Muduli, a delivery driver who lives just outside Orissa's state capital Bhubaneswar, said the whole of his village had spent the night hunkering down in a communal shelter.

"We were all afraid, the whole village was afraid, we didn't know how strong the winds would be," the 43-year-old told AFP in the morning, when the winds had died down and heavy overnight rainfall had ceased.

"Everyone was awake the whole night to see what the size of (the) storm would be and to be on guard."

Pradipta Kumar Mohapatra, Orissa's special relief commissioner, said that seven people were known to have died.

"We can confirm seven deaths in Orissa, mostly due to falling branches from trees," he told AFP in Bhubaneswar.

"Our rescue workers and state officials are working tirelessly to sort things out.

"Electricity and water will be restored everywhere by this evening, except for the district of Ganjam, which has been very badly affected. We are coming up with a separate plan to address the situation in Ganjam."

More than 8,000 people were killed in 1999 when a cyclone hit the same region, devastating crops and livestock. The area took years to recover.

This time round, a massive evacuation operation, which officials said was the biggest in Indian history, appeared to have succeeded in minimising casualties.

"I think we have been successful in minimising the loss of precious lives," Orissa's Chief Minister Naveen Patnaik told reporters in Bhubaneswar.

Some 600,000 people were left homeless after the ferocious storm swept through 14,000 villages mainly in coastal districts, Mohapatra told AFP.

Families, many clutching bags of possessions, or holding their children, returned to what was left of their homes to assess the damage after spending the night in the shelters.

"I lost my house and also a small shaving shop, I lost everything," Janardan, 32, who uses one name, said from inside his tiny dwelling in Gopalpur. The cyclone collapsed the roof, leaving Janardan and his wife to sift through the debris and begin the clean up.

High-sided trucks lying on their sides were witness to the strength of the winds on the main highway south of Gopalpur, which was littered with uprooted trees and other debris.

Despite the damage, there was a general sense of relief that things could have been a lot worse in Orissa and neighbouring Andhra Pradesh.

"We were preparing for a super cyclone, but Phailin did not turn into a super cyclone," spokeswoman for the National Disaster Management Authority (NDMA), Tripti Parule, told AFP.