MANILA, JULY 17 -- Losses from Monday's earthquake on Luzon Island rose today to 309 confirmed dead, with hundreds more injured, and government officials and rescue workers said they feared the toll would climb much higher.

Rescue teams continued to dig through the rubble of collapsed buildings, but a shortage of heavy construction equipment and other emergency supplies hampered their efforts. A Manila television station made repeated appeals for more blood, medicine and rescue equipment for the stricken areas.

U.S. military engineers from Clark Air Base and Subic Bay Naval Station were quick to assist in the rescue effort, bringing cutting torches, jacks, front-end loaders and search dogs to assist poorly equipped Filipino rescue workers.

U.S. teams worked side-by-side with Philippine soldiers to pull survivors from the rubble of a school in Cabanatuan City and set up a 54-bed field hospital there with two intensive-care units. Nine helicopters were made available to airlift the injured to hospitals.

Reporters in the hardest-hit areas said some Philippine rescue efforts appeared disorganized, often consisting of untrained private citizens working with little more than their bare hands.

Eighty-two people were confirmed dead and 386 known injured in the mountain resort city of Baguio, 120 miles north of Manila, following Monday's quake, which registered 7.7 on the Richter scale and lasted about 45 seconds.

By nightfall, more than 50 people were still believed trapped beneath the rubble of Baguio's Hyatt Terraces Hotel, where the upper floors collapsed onto the luxury hotel's atrium-style lobby.

Delivery of rescue materials to the stricken areas was hindered because Baguio's airport was closed, and the narrow, winding highway from Manila was blocked by debris.

Initial reports said that up to 600 people may still be trapped in several collapsed factories in Baguio and up to 100 more pinned beneath the Nevada Inn hotel. However, officials of the Office of Civil Defense here said they knew only of the 50 still trapped at the Hyatt.

"There are cries of children and voices of people in these hotels," said rescue coordinator Rudy Roxas, who spoke to local radio station DZRH via walkie-talkie. "We can't say how many there are, but the rescuers are trying to reach them."

Most stores in the city were reported closed, and residents were running out of food.

Film taken from helicopters showed vast destruction in Baguio, a city of 120,000 residents. The Nevada Inn and the Baguio Park Hotel had both folded like accordions, the roof of the city library had fallen into the street, and thousands of people had camped out in a city park, afraid to enter their homes because of aftershocks.

More than 70 aftershocks have been felt since Monday afternoon's tremor, with two measuring 6.3 and 5.8 on the Richter scale, according to the U.S. Geological Service in Boulder, Colo. Seismologists here warned that more aftershocks were likely.

An American with the U.S. Agency for International Development was still missing in Baguio and believed buried under the rubble of the Nevada Inn, where he had been attending a U.S.-sponsored conference, U.S. Embassy spokesman Stanley Schrager said. Schrager said he had no word on the fate of the 1,500 U.S. citizens who reside in Baguio.

The quake is believed to have left nearly 4,000 families homeless.

In Cabanatuan in Nueva Ecijas province, rescue workers used torches, cranes and bare hands in the search for survivors at the six-story Philippine Christian College, which collapsed. Cabanatuan was close to the epicenter of the quake, the strongest to hit the Philippines in 14 years.

At least 49 people were killed when the old building shook apart while more than 300 students were attending classes.

A total of 179 people were rescued today from the debris of the college, including one young student who told news services that she ate paper and sand while awaiting rescue. Each time a new survivor was dug up, rescue workers and onlookers burst into applause.

At nightfall, 30 to 40 students were still believed pinned beneath the rubble. Rescue workers were planning to continue their search throughout the night, using generators for lighting.

Philippine President Corazon Aquino and several cabinet ministers visited Cabanatuan, where she inspected the damaged college building and talked with survivors. Aquino declared Cabanatuan, Baguio and several other hard-hit areas in Nueva Ecija and Pangasinan provinces to be calamity areas .

Meanwhile, offers of foreign assistance began pouring in to the Philippines.

The U.S. government immediately turned over $25,000 in emergency funds to the Philippine Red Cross. Also, a C-141 plane from Andrews Air Force Base in Maryland is expected to arrive here late Wednesday carrying a search-and-rescue team, dogs and 20 tons of rescue support equipment, according to the U.S. Embassy here.

Offers of aid have also come from Israel, Japan, Britain, Singapore and the Netherlands.

In the capital, the earthquake was felt but did little damage. The Office of Civil Defense said two people were killed in Manila and eight in suburban Quezon City.

The following agencies are accepting cash donations for Philippine earthquake victims:

American Friends Service Committee, Philippines Earthquake Assistance, 501 Cherry St., Philadelphia, Pa. 19102. Call (215) 241-7141.

American Jewish Joint Distribution Committee, 711 Third Ave., 10th Floor, New York, N.Y. 10017. Call (212) 687-6200.

American Red Cross, Philippines Earthquake Disaster, P.O. Box 37243, Washington, D.C. 20013. Call (800) 842-2200.

Grassroots International, P.O. Box 312, Cambridge, Mass. 02139. Call (617) 497-9180.

International Medical Services for Health, 103 Loudon St. SW, Leesburg, Va. 22075. Call (703) 771-0011.

Operation USA, 7615 1/2 Melrose Ave., Los Angeles, Calif. 90046. Call (213) 658-8876.

World Concern, P.O. Box 33000, Seattle, Wash. 98133. Call (206) 546-7201.

World Relief, P.O. Box WRC, Wheaton, Ill. 60187. Call (312) 665-0235.

World Vision, 919 W. Huntington Dr., Monrovia, Calif. 91016. Call (800) 423-4200.

Church World Service, Philippines Earthquake Response, P.O. Box 968, Eklhart, Ind. 46515. Call (219) 264-3102.

U.S. Committee for UNICEF, 333 E. 38th St., New York, N.Y. 10016. Call (212) 686-5522.

Catholic Relief Services, P.O. Box 17220, Baltimore, Md. 10304. Call (301) 625-2220.