San Juan – Puerto Rico on Wednesday faced what officials said could be the strongest hurricane to ever hit the US territory as they warned it would decimate the power company's crumbling infrastructure and force the government to rebuild dozens of communities.Maria barrelled toward the island with 281km/h winds and was expected to make landfall on Wednesday midmorning along Puerto Rico's southeast coast as a Category 5 storm, punishing the island with life-threatening winds for 12 to 24 hours, forecasters said."This is going to be an extremely violent phenomenon," Gov. Ricardo Rossello said. "We have not experienced an event of this magnitude in our modern history."The number of power outages spiked as Maria approached, with the storm centred early on Wednesday about 115km southeast of San Juan, Puerto Rico, and moving northwest at 17km/h, according to the US National Hurricane Centre in Miami.Maria ties for the eighth strongest storm in Atlantic history, when measured by wind speed. Coming in second is this year's Irma, which had 300km/h winds and killed 38 people in the Caribbean and another 36 in the US earlier this month.Power outages, floodingPuerto Rico had long been spared from a direct hit by hurricanes that tend to veer north or south of the island. The last Category 4 hurricane landfall in Puerto Rico occurred in 1932, and the strongest storm to ever hit the island was San Felipe in 1928, with winds of 257km/h.As Maria approached, US President Donald Trump offered his support via Twitter: "Puerto Rico being hit hard by new monster Hurricane. Be careful, our hearts are with you – will be there to help!"More than 4 400 people were in shelters by late Tuesday, along with 105 pets, Rossello said.The storm's centre passed near or over St Croix overnight on Tuesday, prompting US Virgin Islands Gov. Kenneth Mapp to insist that people remain alert. St Croix was largely spared the widespread damage caused by Hurricane Irma on the chain's St Thomas and St John islands just two weeks ago. But this time, the island would experience five hours of hurricane force winds, Mapp said."For folks in their homes, I really recommend that you not be in any kind of sleepwear," he said during a brief news conference. "Make sure you have your shoes on. Make sure you have a jacket around. Something for your head in case your roof should breach... I don't really recommend you be sleeping from 11 o'clock to 4 (am)... Be aware of what's going on around you."Maria killed one person in the French Caribbean island of Guadeloupe when a tree fell on them on Tuesday, and two people aboard a boat were reported missing off La Desirade island, just east of Guadeloupe, officials said.About 40% of the island – 80 000 homes – were without power and flooding was reported in several communities.'The winds are merciless'The storm also blew over the tiny eastern Caribbean island of Dominica late on Monday, where Prime Minister Roosevelt Skerrit sent out a series of dramatic posts on his Facebook page, including that his own roof had blown away."The winds are merciless! We shall survive by the grace of God," Skerrit wrote before communications went down.The storm knocked out communications for the entire island, leaving anyone outside Dominica struggling to determine the extent of damage, though it was clearly widespread. "The situation is really grave," Consul General Barbara Dailey said in a telephone interview from New York.She said she lost contact with the island at about 04:00. At that point, officials had learned that 70% of homes had lost their roofs, including her own.Flooding was a big concern, given the island's steep mountains, cut through with rivers that rage even after a heavy rain. Dominica was still recovering from Tropical Storm Erika, which killed 30 people and destroyed more than 370 homes in August 2015.Forecasters said the storm surge from Maria could raise water levels by 1.8m to 2.7m near the storm's centre. The storm was predicted to bring 250mm to 380mm of rain across the islands, with more in isolated areas.To the north, Hurricane Jose weakened to a tropical storm on Tuesday night. Forecasters said dangerous surf and rip currents were likely to continue along the US East Coast, but said the storm was unlikely to make landfall. Big waves caused by Jose swept five people off a coastal jetty in Rhode Island and they were hospitalised after being rescued.A tropical storm warning was posted for coastal areas in Rhode Island and Massachusetts, and tropical storm watches were up for parts of New York's Long Island and Connecticut.