KHULNA, Bangladesh (AP) -- A powerful cyclone packing 150 mph winds slammed into Bangladesh on Thursday night, flattening homes, toppling trees and power poles, and forcing hundreds of thousands of people to flee for shelters in this low-lying nation.
Tropical Cyclone Sidr swept in from the Bay of Bengal, buffeting the southwestern coastal areas within a 155-mile radius of its eye with heavy rain and storm surges predicted to reach 20 feet high.
No casualties were immediately reported, but rescue teams were on standby.
Sidr's eye crossed the Khulna-Barisal coast near the Sundarbans mangrove forests, the Bangladesh Meteorological Department said.
At least 650,000 people fled to evacuation centers and 3.2 million people were expected to be evacuated in all, said Ali Imam Majumder, a senior government official in Dhaka, the capital.
``We have taken all precautions,'' Majumder said. Authorities dispatched food, medicines, tents and blankets to the affected areas and suspended operations at the country's two main seaports _ Chittagong and Mongla _ while ferry services and flights were halted across the coastal region. Ships were warned to return to shore.
In the coastal districts of Bagerhat, Barisal and Bhola, residents said the storm flattened thousands of flimsy straw and mud huts, flooded low-lying areas and uprooted trees and electric poles.
``We sitting out the storm by candlelight,'' Bagerhat resident Bishnu Prashad said by phone.
In the capital, incessant rain flooded some streets, stranding vehicles, while strong winds sent billboards flying.
Bangladesh, a low-lying delta nation, is prone to seasonal cyclones and floods that cause huge losses of life and property. The coastal area borders eastern India and is famous for the mangrove forests of the Sundarbans, a world heritage site that is home to rare Royal Bengal Tigers.
Selva Sinnadurai, head of the International Committee of the Red Cross in Bangladesh, said many people would have to take refuge in schools, community centers and other public buildings because there aren't enough cyclone shelters _ concrete buildings on raised pilings.
``Having said that, we are quite sure with this kind of impact that the damage on property and farmland could be extensive,'' Sinnadurai told CNN Thursday.
Some took refuge in ``mud forts'' built along the coast to resist tidal surges.
The storm was also likely to trigger flooding along coastal areas of West Bengal and Orissa states in eastern India, forecasters said.
The cyclone caused heavy rain and high winds across much of southern and central Bangladesh. It was likely to weaken into a tropical storm as it moved across the country to the northeast.
Many of the fishing boats in the region's coastal waters put down anchor at nearby shoals and islets that dot the South Asian country's shoreline.
Communications with remote forest areas and offshore islands were temporarily cut off.
The sea resort of Cox's Bazar was deserted after Wednesday's warning. Dozens of tourists were stranded in the offshore coral atoll of St. Martins as rough seas forced cruise boats and ships to stay ashore.