GUATEMALA CITY - An Alaskan woman was beaten by a mob armed with machetes, sticks and stones, the victim of growing fears that Americans are stealing Guatemalan children for their organs.

Guatemala has been rife with rumors that Americans are abducting children. There also have been allegations - characterized as groundless by Washington - that kidnapped Guatemalan children are put to death on arrival in the United States and their body parts sold for transplant purposes.

Earlier in March, Melissa Carol Larson, a tourist from New Mexico, was chased by a mob that suspected she was trafficking in organs.

Officials identified the woman beaten yesterday as Diane Werntock Jung, 52, of Alaska. They gave no hometown. She was in serious condition at a hospital in Coban, about 75 miles north of the capital. Coban Fire Chief Mauro Rene Ac Chun said Jung had been stabbed eight times and had a broken arm, a probable skull fracture and other injuries.

Witnesses said the crowd - armed with machetes, sticks and stones - gathered in the main plaza in San Cristobal Verapaz after an Indian woman screamed that Jung had tried to steal her 8-year-old boy. The boy, who had been missing, turned up later.

Jung took refuge in a judge's office in a municipal building, but the mob overpowered police, said Roberto Alvarado, a reporter for Radio Coban who witnessed the attack.

Witnesses said the mob set the building on fire, ignoring pleas from local officials and a local Catholic bishop. Jung was rescued by firefighters and rushed to Coban, a town 18 miles away.

The army sent troops in a few hours later to restore order and arrested about 15 people, according to Eduardo Sam Aldana, another radio reporter.

Reports of the sale of organs of kidnapped Third World children have been around for years, first surfacing in Honduras in early 1987. U.S. officials say the allegations became an integral part of Soviet and Cuban anti-U.S. propaganda.

Adoptions by Americans in Guatemala average about 10 a week, and suspicions about the practice are fed by child stealing and baby trafficking in the country.

The U.S. Embassy said a senior Public Health Ministry official, Guillermo Carranza Targena, has inflamed the situation by suggesting that some unscrupulous traffickers are U.S. citizens.