Hurricane Emily battered Mexico's Caribbean beach resorts yesterday, forcing thousands of tourists out of fancy seafront hotels and into crowded shelters to escape its destruction.

Emily knocked out power lines, blew down trees and whipped up dangerous waves at the popular resort of Cancun and along the Maya Riviera, normally a vacation playground of long, white beaches and calm seas.

There were no early reports of injury or death.

After killing at least four people in its swing across the Caribbean, Emily hit Mexico's coast as a Category 4 hurricane with winds of 215 kph.

Emily lost some punch as it moved inland, dropping to a Category 2 hurricane with winds near 175 kph, but forecasters said it would probably gather new strength when it heads out over the Gulf of Mexico.

Mexico shut down most of the offshore wells in its most productive oil fields in the Gulf of Mexico, and two major ports that export crude.

Thousands of tourists cut short their beach vacations and fled for home over the weekend. But many were unable to leave or decided to see it through at makeshift shelters.

Luxury beachfront hotels were boarded up, so inland hotels put up the 5-star refugees as well as local residents. Some squeezed in 15 people per room and schools and gymnasiums were also used in the operation to protect about 60,000 people.

Soldiers packed 2,000 visitors from three luxury hotels into one gymnasium in Cancun and simply barred the doors.

"I am dying here," screamed Spanish tourist Juan Moreno, 27, from Madrid as he banged on a locked iron gate. There was no fan or air-conditioning, and hotel staff tied to calm down a woman who was hyperventilating.

Many locals who live in ramshackle houses feared for their homes as they packed a few possessions and headed for shelter.

"We live on a ranch about 10 km from here and I don't know if the roof is going to bear up. We left everything covered by tarpaulins," said Ezequiel Martinez a welder taking refuge in Playa del Carmen.

Many feared a repeat of Hurricane Gilbert, which tore up Cancun in 1988, flattening homes and killing hundreds.

Emily killed four people when a car was swept away by flood waters in Jamaica on Sunday. A man also died in a mudslide in Grenada.

Two pilots were also killed in Mexico on Saturday night when their helicopter was blown by a gust of wind into the Gulf of Mexico during oil rig evacuations.

State oil company Pemex cut off most oil production in the Campeche Sound, the Gulf of Mexico basin that produces 80 per cent of Mexico's crude, and some 15,000 oil rig workers were evacuated.

Oil prices jumped in response to the supply cut.

Hurricane watches were issued yesterday for the south Texas coast and north-eastern Mexico, where Emily is expected to make landfall early tomorrow morning after crossing the Gulf of Mexico.