VILLAHERMOSA, Mexico -- Air and sea search teams intensified their hunt Saturday for 10 missing oil workers as Tropical Storm Nate headed west, threatening new areas of Mexico's gulf coast where hurricane conditions are expected.
Meanwhile, fishermen groups reported that at least a dozen of their colleagues aboard two Mexican shrimp boats went missing in the gulf on Friday.
Nate was still moving toward the coast very slowly, but was expected to pick up some speed Saturday, said the U.S. National Hurricane Center in Miami. Forecasters said the storm would reach the coast Sunday, mostly likely with near hurricane intensity.
Helicopters from the Mexican navy and the state oil company, Petroleos Mexicanos, left ports along the coast of Tabasco state to scour the sea, while other crews searched the beaches closest to the spot where the 10 abandoned their disabled liftboat for an enclosed life raft in the storm about midday Thursday.
"The hope is that we find them alive at sea," said one navy rescuer searching the beach at Frontera on the Tabasco coast. He didn't give his name because he wasn't authorized to speak to the news media.
By Saturday afternoon, authorities said they still had found no sign of the workers, who were employees of Houston-based Geokinetics Inc. and who called for help Thursday afternoon after leaving a vessel known as Trinity II.
The missing include four U.S. workers, four Mexican workers, one worker from Kazakhstan and a 10th of unconfirmed nationality.
Mexico's National Water Commission reported that the rain had diminished significantly in the Bay of Campeche where the workers disappeared as Nate raged more than 120 miles (200 kilometers) away from the area, threatening the coast of Veracruz state.
A liftboat can lower legs to the sea floor and then elevate itself above the water level. This one was being used as a recording vessel and housing for the crew, and it was in waters about 25 feet (8 meters) deep.
Randy Reed, president of the vessel's owner, Trinity Liftboat Services LLC in New Iberia, Louisiana, was not available for comment Saturday, according to a woman who answered the phone there. The Mexican navy said Friday night that sailors had reached the 94-foot (29-meter), 185-ton Trinity II but found no crew.
Geokinetics spokeswoman Brenda Taquino said the life raft was a sealed capsule containing enough food and water to last for several days, but there was no way to communicate with it.
Meanwhile, fishermen associations of Campeche reported that two shrimp boats have been missing since Friday along with at least a dozen people. They were in the gulf heading to the state of Tamaulipas when they were surprised by the tropical storm.
Weather forecasters say Tropical Storm Nate is growing stronger and could be near hurricane strength when it hits Mexico on Sunday.
The National Weather Service said at 4 p.m. (21:00 GMT) Saturday that Nate was centered 120 miles (195 kilometers) east-northeast of Veracruz, with maximum sustained winds increasing to 65 mph (100 kph). It was inching westward and winds will strengthen in the next 24 hours, the service said.
A hurricane warning was posted along the coast from Tuxpan to Veracruz and a hurricane watch from south of Veracruz to Punta El Lagarto. The service said the government should act to protect life and property.
Pemex said it had evacuated 473 workers from platforms off the coasts of the gulf coast states of Veracruz and Tamaulipas. Mexico's gulf ports were closed to navigation.
Veracruz state officials also ordered schools closed Monday as a precaution.
Meanwhile, former Hurricane Katia has been downgraded in the far north Atlantic, and the remnants of Maria are barely a tropical cyclone in the Caribbean.
The National Hurricane Center says Katia is still expected to bring strong winds to the British Isles on Monday. The storm was centered about 300 miles (475 kilometers) east-southeast of Cape Race, Newfoundland.
Forecasters said Maria was about 310 miles (500 kilometers) east-southeast of San Juan, Puerto Rico, with winds reaching 40 mph (64 kph).