The Philippine government revised the official death toll from Typhoon Haiyan up to 1,744 Tuesday, and the final death toll is expected to be even higher.
The country's Natural Disaster Risk Reduction and Management Council also said Tuesday that 2,487 people had been injured when the storm barreled into the eastern islands of the Philippine archipelago Friday. Officials had estimated over the weekend that the disaster might have killed at least 10,000 people in one province alone and displaced 660,000 others. 
U.S. Marines landed Monday at some of the worst-hit areas, bringing water, generators and other critical supplies to survivors.
Two U.S. C-130 transport planes filled with relief necessities and a contingent of troops flew from Manila's Vilamor air base to the city of Tacloban, on the eastern seaboard, which was heavily damaged in what may prove to be the deadliest storm in the history of the Philippines.
The members of the 3rd Marine Expeditionary Brigade were among the first outside help in what is expected to be a major aid mission in coming days and weeks.
"I don't believe there is a single structure that is not destroyed or severely damaged in some way — every single building, every single house," U.S. Marine Brig. Gen. Paul Kennedy said after taking a helicopter flight over Tacloban, the largest city in Leyte province. He spoke on the tarmac at the airport, where the two cargo planes were parked, engines running, unloading supplies.
"We saw bodies everywhere," he said. Some were floating in the water, others in a schoolyard.
He said trees were uprooted for miles around, roads were impassable and power lines were down.
"I don't know how else you can describe total devastation," Kennedy said at the Tacloban airport. 
The Pentagon said another 90 troops were on their way.
The United States also said Monday it is providing $20 million in aid to the ravaged nation, and the USS George Washington, currently in Hong Kong, was making final preparations to deploy to the Philippines. 
The carrier will be joined by other support ships assigned to deliver humanitarian relief aid, including medical supplies, food, water and temporary shelters. The carrier, which holds 5,000 sailors and more than 80 aircraft, was expected to arrive in the next 48 to 72 hours.
Disrupted transportation and communications links have made it difficult to count the dead and distribute relief goods. Destruction from the typhoon, which slammed into the central Philippines was extensive, with debris blocking roads and trapping decomposing bodies.
Meanwhile, the Philippine National Red Cross said Monday its search and rescue efforts are being hampered by looters, including some who attacked trucks of food and other relief supplies the agency was shipping from a port city.
Rescuers also faced blocked roads and damaged airports on Monday as they raced to deliver desperately needed tents, food and medicines to the eastern Philippines.
Police guarded stores to prevent people from hauling off food, water and such non-essentials as TVs and treadmills, but there was often no one to carry away the dead -- not even those seen along the main road from the airport to Tacloban.
With other rampant looting being reported, President Benigno Aquino III said Sunday that he was considering declaring a state of emergency or martial law in Tacloban.
Authorities said at least 9.7 million people in 41 provinces were affected by the typhoon, which is called Yolanda in the Philippines but is known as Haiyan elsewhere in Asia. It's one of the most powerful recorded typhoons to ever hit land, with winds gusting up to 175 miles per hour, making it the equivalent of a category 4 hurricane. At least 23,000 houses had been damaged or destroyed. Ships were tossed inland, cars and trucks swept out to sea and bridges and ports washed away.
Regional police chief Elmer Soria said he was briefed by Leyte provincial Gov. Dominic Petilla late Saturday and was told that there may be 10,000 deaths in Leyte province, mostly due drowning and injuries suffered from collapsed buildings. The governor's figure was based on reports from village officials in areas where the storm hit.
Meanwhile, a tropical depression, named Zoraida, entered the southeast region of Mindanao, an area roughly 150 miles south of Tacloban, the Philippine Star reported. The storm was expected to make landfall along the border of Surigao del Sur and Davao Oriental Tuesday afternoon, and could bring moderate to heavy rains, Philippine authorities told the newspaper.
The new disturbance, however, is not expected to be as powerful as last week's typhoon.
Fox News' Justin Fishel and The Associated Press contributed to this report.