ARANSAS PASS, Texas: An overturned trailer sits in a park in the wake of Hurricane Harvey yesterday. - AP

CORPUS CHRISTI, United States: Hurricane Harvey left a trail of devastation yesterday after the most powerful storm to hit the US mainland in over a decade slammed into Texas, destroying homes, severing power supplies and forcing tens of thousands of residents to flee. Harvey roared ashore late Friday, first pummeling the town of Rockport as a category four hurricane, packing sustained winds of 215 km per hour. A few hours later it made a second landfall just north of Rockport as a Category Three hurricane, with winds of 125 mph, the National Hurricane Center said.

Over the next hours Harvey lost strength as it moved inland over south Texas and eventually dropped to a still-dangerous Category One storm, with winds of 75 miles per hour. Although the NHC said Harvey was likely to become a tropical storm later in the day, experts said that a vast area of Texas would face potentially devastating floods over the coming days while some communities were hit by localized tornados. Emergency services were struggling to make headway as rains continued to lash down while the coast guard was responding to May Day calls from tugboats caught out at sea.

President Donald Trump, aware of the damage to George W Bush presidency's for his tardy response to Hurricane Katrina, said he was closely monitoring the relief efforts and urged everyone to "Be Safe!" "There's widespread devastation. We had businesses and homes that are completely destroyed, and certainly a number of lives that have been disrupted significantly," said CJ Wax, the mayor of Rockport. "We have cross-functional teams that are out trying to assess the damage and determine what is needed to begin the recovery process, but it is still tropical storm-force winds and blinding rain," he told MSNBC.

Rockport's local airport was among the places to suffer major damage, with a light aircraft crushed by a building collapse. Homes were also burnt to the ground as power cables caught fire. Around 190,000 customers were without power in Rockport and the nearby town of Corpus Christi while another 62,000 were without power in Houston, the state's largest city.

While most residents did heed advice to flee the worst-hit areas, some hunkered down for the night in Corpus Christi, in buildings that seemed to bend in the wind. "I've never seen anything like this. We do have strong winds - we're right next to the bay - but nothing like last night," Brandon Gonzalez, who owns a store in the town, told AFP. "I mean, I was even a little bit terrified of what was going to happen. Our building was just shaking back and forth. It really got bad. I think we held up pretty good though."

While the damage in Houston was less extensive, the suburb of Sienna Plantation suffered an apparent tornado hit which knocked down walls and tore tiles off roofs, according to the local KTRK network. While there were no immediate reports of casualties, the Coast Guard was responding to Mayday calls from three tugboats near Port Aransas. "Coast Guard Air Station Corpus Christi directed the launch of two MH-65 Dolphin helicopter aircrews that are en route for rescue," it said in a statement.

Brain McNoldy, a hurricane expert at the University of Miami, said a strong ridge of high pressure was preventing the storm from dispersing. "You would expect the hurricane to just keep going inland over Texas, but that ridge coming into place there is just stopping everything from moving and that's what's going to keep Harvey in place for the next days," he told AFP. "A tropical cyclone - it could even be a depression it doesn't matter - makes a lot of rain, so if that sits over you for one day, two or three or four you just keep accumulating rain. It may stay three or four days, and even up to six days. There's no sign of it really moving in a foreseeable future."

The NHC warned of likely "catastrophic and life-threatening flooding" due to the massive rainfall forecast and the huge storm surge, which could reach nearly four meters in some places. Trump granted Texas Governor Greg Abbott's request to declare a "major disaster" zone in the state to speed federal aid to the millions in harm's way. Abbott in turn activated more than 1,000 National Guardsmen to help with evacuation and recovery.

After authorities issued a series of alerts about the dangers from the storm, supermarket aisles were stripped bare, while homes and shops had boarded up windows. Coastal Texas is a fast-growing area, with some 1.5 million people moving into the region since 1999. It is also home to a large number of oil refineries.

US authorities said about 22 percent of crude production in the Gulf of Mexico, accounting for more than 375,000 barrels a day, was shut down as of Friday. Harvey is the most powerful hurricane to hit the mainland since Wilma struck Florida 12 years ago. 2005 was a huge year for hurricanes - before Wilma, Hurricane Katrina pummeled New Orleans, leaving more than 1,800 dead.

The then-president Bush faced severe criticism after federal authorities appeared unprepared for the devastating damage inflicted by Hurricane Katrina. Wary of any accusation of complacency, Trump said he was fully engaged with relief efforts. "Closely monitoring #HurricaneHarvey from Camp David. We are leaving nothing to chance. City, State and Federal Govs. working great together", he wrote on Twitter.

Many residents who fled the worst-affected areas headed for the city of San Antonio, where temporary shelters are run by the fire department. "I felt like I didn't want what happened to the guys in New Orleans... I didn't want that to happen to me," Michael Allen, an evacuee from Corpus Christi, told AFP. "I only got what you see me with. Everything I had, I had to leave. Everything. It was, bring it with me or lose my life and I felt like I should save my life." - AFP