Two tourists from Toronto are among the dead in a fiery helicopter crash that claimed the lives of five people in Hawaii.

U.S. federal officials are investigating after the helicopter, carrying four tourists and the pilot, crashed into a mountain ridge on Hawaii's Molokai island near an elementary school amid rainy weather.

The operator of the helicopter, Blue Hawaiian Helicopters, said the passengers were two men and two women that were on a 45-minute tour that initially departed from Kahului, on Maui.

"We're extremely grieved for our pilot as well as the passengers," Blue Hawaiian Helicopters owner David Chevalier told The Associated Press. "Something like this can't be more devastating to us."

The incident occurred shortly after noon local time on Thursday. Firefighters have recovered four bodies, while a fifth was found trapped under the wreckage.

Maui County spokesperson Rod Antone said the passengers were from Pennsylvania and Ontario.

He said the pair from Pennsylvania were newlyweds, but the relationship between the Toronto tourists, a man and a woman, hasn't been confirmed.

The Honolulu Star-Advertiser has identified the pilot as Nathan Cline, 30, of Kihei, Maui. Blue Hawaiian Helicopters listed Cline as having logged more than 4,000 flight hours.

The crashed helicopter was a Eurocopter model EC-130 B4 that was less than a year old, Chevalier said.