MANAGUA, Nicaragua - The heart of powerful Hurricane Eta began moving ashore in Nicaragua on Tuesday with potentially devastating winds and rains that have already destroyed rooftops and caused rivers to overflow.

The hurricane had sustained winds of 140 mph (220 kph), according to the U.S. National Hurricane Center.

The eyewall was touching the coast, even if the centre of the Category 4 hurricane was still about 20 miles (35 kilometres) south-southeast of Bilwi, or Puerto Cabezas. It was MT) and moving west at about 3 mph (6 kph).

Guillermo Gonzalez, director of the country's emergency management agency, said in a news conference that as Eta began to make landfall there were reports of corrugated metal roofs flying off homes, trees, poles and power lines falling and rivers rising in the coastal area. So far, there were no reported injuries or deaths, he said.

Bilwi, the main coastal city in the region. About 10,000 people were in shelters in that city and an equal amount were sheltered in smaller towns across the region, he said. The area had already been lashed with strong winds and heavy rain for hours as the storm's eye hoved just offshore.

Authorities in Nicaragua and Honduras had moved people Monday from outer islands and low-lying areas to shelters. Residents scrambled to shore up their homes, but few structures along Nicaragua's remote Caribbean coast were built to withstand such force.

Nicaragua's army moved red-helmeted troops specialized in search and rescue to Bilwi, the main coastal city in an otherwise remote and sparsely populated area. The navy spent Monday ferrying residents of coastal islands to shelters in Bilwi, also known as Puerto Cabezas.

At a shelter in Bilwi, farmer Pedro Down waited late Monday for Eta's arrival. “When it comes it can rip off all the (roof) and destroy the house, so you have to look for a safer place,” he said, cradling a baby in his arms. “So I came here to save our lives.”

On television Monday, Nicaragua Vice-President and first lady Rosario Murillo prayed for God to protect the country. She said Nicaragua would apply lessons learned from previous storms. “How many hurricanes have come and we have moved on, thanks to God,” she said.

Along Honduras' northern Caribbean coast, torrential rains from Eta's outer bands caused some rivers to overwhelm their banks Monday, forcing evacuations.

This could be only the beginning of Eta's destruction. The storm was forecast to spend the week meandering over Central America dumping rain measured in feet not inches.

Forecasters said central and northern Nicaragua into much of Honduras could get 15 to 25 inches (380 to 635 millimeters) of rain, with 35 inches (890 millimeters) in isolated areas. Heavy rains also were likely in eastern Guatemala, southern Belize and Jamaica.

A storm surge of around 15 feet (4.5 metres) above normal tides was possible for the coast of Nicaragua, forecasters said.

The quantities of rain expected comparisons to 1998's Hurricane Mitch, one of the most deadly Atlantic hurricanes in history. An archival report from the National Hurricane Center said Mitch led to the deaths of more than 9,000 people.

Eta tripled in strength in about 24 hours, rapidly intensifying from a 40 mph (65 kph) storm Sunday morning to a 120 mph (190 kph) hurricane around midday Monday, and continuing to gain power throughout the day.

It is the eighth Atlantic storm this season to hit the meteorologists' definition for rapid intensification - a gain of 35 mph (56 kph) in wind speed in just 24 hours. It's also the fifth to reach major hurricane status. Over the past couple of decades, meteorologists have been increasingly worried about storms that just blow up in strength.

Eta is the 28th named Atlantic storm this season, tying the 2005 record for named storms. It's the first time the Greek letter Eta has been used as a storm name because after the 2005 season ended, meteorologists went back and determined a storm that should have been named wasn't.

Hurricane season still has a month to go, ending Nov. 30. In 2005, Zeta formed toward the end of December.

Associated Press writers Marlon Gonzalez in Tegucigalpa, Honduras and Christopher Sherman in Mexico City, and AP Science Writer Seth Borenstein in Washington contributed to this report.