NEW DELHI, India (AP) _ Flames and smoke raced through a 10-story luxury hotel before dawn today and officials said at least 38 people, including one American, were killed in the fire. Some plunged to their deaths from the second and third floors when they tried to escape.

A U.S. Embassy official, speaking on condition he not be identified, said the blaze at the Siddharth Continental Hotel killed one American. He refused to release the man's name pending notification of his family, but hospital sources identified the victim as Richard Arnell. No hometown was available.

A spokesman for the relief organization CARE in New York said Christopher Roesel, 37, who works for the relief organization in Thailand, was recovering from smoke inhalation in a hospital. The official, Bill Dugan, said five other CARE staffers escaped the fire without injury.

A U.S. Embassy spokesman earlier said six U.S. citizens registered at the hotel escaped injury.

At a news conference late today police said 46 people were injured and 38 remained hospitalized. Officials earlier said 70 people had been hurt.

Though no cause for the blaze was established, police and hotel personnel speculated an electrical short-circuit may have set a carpet afire in the hotel's ground-floor banquet room.

Survivors claimed no alarm was given and that the staff and fire department were poorly prepared for an evacuation.

''Nobody told us anything,'' said Phillipe Demerey, a businessman from Liege, Belgium. ''I looked out my window and saw the flames. I opened the door and the hall was full of smoke. I left the hotel through the fire escape with only my nightclothes. I saw people shouting for help. It was not very efficient the way they tried to help them.''

New Delhi Lt. Gov. H.L. Kapur said 38 bodies had been recovered. Hospital sources said the dead included about 20 foreigners, including three Britons, two Japanese, two Australians, an Iraqi and at least one Soviet.

Police said two diplomats, from West Germany and Argentina, also died. The United News of India news agency said the victims included two infants.

Authorities opened an investigation of the southern New Delhi hotel for possibly causing death due to negligence, a legal formality that allows a criminal investigation. No arrests have been made.

The hotel is owned by Siddharth Intercontinental Hotels Ltd. of India, and is not affiliated with the Worldwide Intercontinental chain. The United News of India news agency had identified the hotel as Intercontinenta l.

Police Commissioner Ved Marwah said ''all aspects'' of the fire would be investigated, including the possibility of sabotage.

Officials said the fire apparently began at 1:45 a.m. in the banquet room, that flames engulfed the first three floors and sent thick smoke through the floors upstairs.

''There was a stampede and all night the people were running helter- skelter,' ' said an officer at the New Delhi police control room. Officials said most of the dead suffocated or were killed by smoke inhalation. ''We found bodies on every floor,'' said a police officer who spoke on condition he not be identified. ''Some of them were in their beds, others in the hallway.''

But a doctor at Safdarjang Hospital, where the injured and dead were taken, said at least five people died of injuries suffered when they jumped from the hotel's second and third floors. At least one person died of burns, he said.

Staff members said the hotel was ''practically full'' with about 175 guests, about 40 percent of them foreigners.

George Allen, a businessman from Britain, said some guests tried to escape by tying bedsheets together and lowering themselves to safety.

''People were climbing down on sheets,'' he said, ''but some of them caught fire. The fire brigade arrived but there was no water in the tanks. It was 20 minutes before they started to do anything.''

United News of India quoted J.S. Malhotra, general manager of the hotel, as saying an alarm went off soon after staff members working in the cafeteria discovered the blaze. He was quoted as saying many guests did not hear the alarm because they were asleep.

The hotel's architect, S.C. Jain, was quoted by UNI as saying the staff was unable to awaken guests by telephone because electrical power was deliberately cut to prevent the fire from spreading through the electrical system.

Hotel employees said the banquet room, which was gutted, was used for a Jordanian Embassy reception the previous night but was not in use when the fire broke out. Firefighters said four bodies were found in the room.

District Commissioner of Police Maxwell Perrera said 37 of the 70 injured had been hospitalized for various reasons, including smoke inhalation.