Isa Alvarado, spokeswoman for the Public Ministry morgue in Honduras, said the dead were three American women aged 20, 21 and 45.
They were identified as students Daniella Moffson and Olivia Erhardt, and nurse practitioner Abigail Flanagan who worked at the Columbia University Medical Center and was also a General Studies student.
Twelve more Americans were injured. Reinaldo Canales, administrator for the Valle de Angeles Adventist Hospital, said they were in stable condition.
U.S.-based Global Brigades, which organizes international health and development missions, posted a notice on its website saying the accident involved a bus transporting “Columbia University students and other volunteers,” and that those killed were two students and a health care professional.
Columbia later issued a statement saying the vehicle was also carrying students from Barnard College, a women’s liberal arts institution that is affiliated with the university and is located just steps away from its campus in upper Manhattan.
“Our heartfelt sympathy goes out to all those affected by this tragedy,” said the Global Brigades statement, attributed to co-founder Steven Atamian. Phone messages left at the organization’s headquarters in Seattle were not immediately returned.
The crash took place on a highway east of the Honduran capital, Tegucigalpa. Officials reported that the bus was traveling from the town of San Juancito when it veered off a road and fell at least 260 feet (80 meters) into a ravine.
Firefighters’ spokesman Capt. Gustavo Barahona said the crash was believed to be the result of mechanical failure.
He added that at the time of the accident, they were on their way to the airport to return to the United States after carrying out a health mission for poor residents of San Juancito and Valle de Angeles.
Alvarado said forensic workers were preparing the bodies to be returned to the United States.
The U.S. Embassy in Honduras said in a statement it was in close contact with local authorities and working to provide consular assistance to any who need it.