Emergency supplies started flowing into typhoon-devastated areas of the Philippines on Thursday, with a U.S. aircraft carrier group bringing helicopters to ferry in medicine and water.

But the aid effort was still so short-handed that bodies lay uncollected in the hot sun, and injured survivors of Typhoon Hainan had to wait in line for treatment of gashed limbs.

In Tacloban, one of the worst-hit areas, Mayor Alfred Romualdez oversaw a mass burial of victims. As the bodies were being lowered into the ground, thunder rumbled and a sudden storm dumped rain on the grieving workers and onlookers.

“Everybody is traumatized by what happened,” a 23-year-old government employee said. She declined to give her name.

The Red Cross said that the preliminary number of people reported missing since the typhoon was 22,000, according to Reuters. But the relief organization cautioned that the figure could include people who were subsequently located.

In its latest report on the situation, the U.N. Office for the Coordination of Humanitarian Affairs put the confirmed death toll at 4,460 and said 921,200 people were displaced, out of a total of 11.8 million people affected. It said 243,600 houses were destroyed and that fuel in Tacloban was expected to run out in days.

Six days after the storm churned through the central islands of the Philippines, bringing with it a tsunami-like wall of water, there were still shortages of body bags, gasoline and personnel to collect the dead. In Tacloban, corpses were piled on the grounds of the Balyuan Amphitheater. Twenty more lay on the ground at a traffic junction, on a road leading to Samar.

On the shoreline of Cancabato Bay, beneath the sprawling, once manicured grounds of the Leyte Park Hotel, more than 30 bodies were still waiting to be picked up.

The ramped-up relief effort in the Philippines has brought aid to tens of thousands of victims, but it has also illustrated the vastness of this disaster — which spans several hundred miles of islands and includes areas yet to be accessed.

[Photos: Typhoon Haiyan slams the Philippines.]

The disaster has reduced Tacloban, once a bustling provincial capital of 220,000, to a broken landscape of denuded hills and brown rot. Government buildings are abandoned and torn apart, and the stink of decay fills the air. With power out everywhere, miles of downed electrical wires have been repurposed as makeshift laundry lines, on which residents hang soaked remnants of clothing and bedding.

Dazed survivors hunt for loved ones who had vanished in the storm surge. Rizalde Bañares, 40, said he was searching for the bodies of his wife and his 5- and 7-year-old children. He said he found the corpse of his 9-month-old son, Rafael, earlier in the week, after a neighbor heard a report that a baby’s body had been discovered.

“We went to the place and found my son’s body on a pile of debris of trunk, leaves and rubbish,” Bañares said. “The person who had found him on the bend of Binahaan River took him to the higher ground, away from the overflowing riverbank.”

Bañares said he had buried the child along with 20 other bodies at a local church.

[Read: You can’t stop a storm surge.]

A U.S. Navy aircraft carrier, the USS George Washington, and several accompanying ships reached the Philippines on Thursday and began assisting in relief efforts, the U.S. 7th Fleet said in a statement. The U.S. military transported nearly 2,000 gallons of water and three pallets of food to Tacloban’s airfield and sent pallets of clean drinking water to the airfield in Guiuan, a former U.S. Navy air base in Eastern Samar. One of the U.S. ships was headed to another devastated area, Ormoc, which is on the same island as Tacloban. The carrier strike group carries 5,000 service members and 21 helicopters.

The Red Cross has provided about 2,000 body bags to Tacloban. It dispatched six ambulances as well as several water tanks, which arrived Thursday after a four-day trek from Manila.

But the needs are still immense. Patients lined up at clinics seeking treatment for gashes from broken glass and corrugated iron roofing that had flown through the air during the typhoon. Ryan Jay Jopia, health services manager of the Philippine Red Cross, said medical supplies were supposed to be pre-positioned in Tacloban in advance of the storm. But they were nowhere to be found, he said.

Government officials say more than 1,000 military personnel have been deployed to restore order, and in Tacloban, police have imposed an evening curfew. But about 10 miles outside the city Tuesday, a mob ransacked a government building storing packages of rice, Rex Estoperez, a spokesman for the National Food Authority, said in a telephone interview.

The incident illustrated the problems with the hasty relief efforts, Estoperez said. The packages of rice were not piled securely, and when the mob entered the building, the rice bags collapsed, knocking over a wall and killing eight of the looters. The others in the mob walked out with whatever they could grab — amounting to thousands of sacks of rice, which they are trying to resell locally.

“We’re asking the people who took the rice to share it with the victims instead of selling it and doing business,” Estoperez said.

[Videos show storm’s devastating path.]

The Philippines has never conducted a relief operation of such magnitude, Jose Rene Almendras, a cabinet secretary, told reporters.

There are some signs of progress. In the town of Ormoc, aid workers said the police presence is heavy and that security is not a problem.

Two airports in the disaster zone reopened Wednesday, giving new options for transport planes, aviation officials said. Water-purification equipment was flown into Tacloban on Wednesday, and newly installed beacons and runway lights allowed for nighttime takeoffs and landings for the first time since the disaster.

In a statement Wednesday, President Obama encouraged Americans “who want to help our Filipino friends to visit whitehouse.gov/typhoon, which offers links to organizations working in the Philippines and ways to support their efforts.”

“The friendship between our two countries runs deep, and when our friends are in trouble, America helps,” Obama said.

U.N. humanitarian chief Valerie Amos toured Tacloban on Wednesday and told reporters afterward that although a significant amount of material was brought in, much more remains to be done. Her office has released $25 million in emergency relief funds; countries around the globe are pledging to send millions in assistance.

“The priority has got to be — let’s get the food in, let’s get the water in,” Amos said, according to the Associated Press. “We really need to scale up [the] operation.”

Some Philippine officials are indicating that the death toll might be substantially lower than initially feared. President Benigno Aquino III told CNN on Tuesday that the final figure might not top 2,500. But that estimate was overtaken Thursday by the U.N. figure of 4,460 dead.

Aquino’s spokeswoman said Wednesday in a phone interview that it is difficult to be sure, and some aid workers have reported towns with thousands of people dead or missing. Estimates of the dead were as high as 10,000 early in the week.

“I wouldn’t put too much into the figures,” the spokeswoman, Abigail Valte, said. “There are a number of areas we haven’t been able to reach, and we haven’t been able to collate the information.”

Harlan reported from Cebu, Philippines.