At least four people are dead after two floatplanes collided in flight Monday afternoon near Ketchikan, Alaska, the US Coast Guard says.
The Coast Guard, which is leading the investigation, is reportedly still searching for two people.
The passengers on both planes were from the Royal Princess cruise ship, which is on a seven-day cruise.
In a statement to CNN, Princess Cruise Lines said five people were dead and "one guest still unknown." According to CBS News, the cruise line said all five people (four passengers and the pilot) on one of the planes, which was flying on an independent tour, were killed.
A source familiar with the situation told CBS News that both planes are submerged in water. Investigators reportedly believe that one came to rest in a lake, and the other in the ocean. It's unclear how far apart the aircraft are.
An investigative team from the National Transportation Safety Board in Washington, D.C. is expected to arrive in Ketchikan Tuesday afternoon, spokesman Peter Knudson said.
The floatplane collided under unknown circumstances, Federal Aviation Administration spokesman Allen Kenitzer said in an email to The Associated Press. Floatplanes have pontoons mounted under the fuselage so they can land on water.
Eleven people were on one plane, a single-engine de Havilland Otter DH-3, when it went down as it returned from Misty Fjords National Monument, which is part of the Tongass National Forest. Ten people were taken to a Ketchikan hospital.
All patients were in fair or good condition, PeaceHealth Ketchikan Medical Center spokeswoman Marty West said.
The second plane was a single-engine de Havilland DHC-2 Beaver, Coast Guard Lt. Brian Dykens said, adding that three people from that aircraft died.
It was unclear which plane carried the fourth victim, whose body was recovered during a Monday night search.
"It's been a long day and the crews have been working really hard to rescue people and recover the deceased," Deanna Thomas, a spokeswoman for the Ketchikan Gateway Borough, the local government, said Monday evening.
A spokeswoman for Taquan Air, operator of the Otter, said the company had suspended operations while federal authorities investigate the deadly crash.
"We are devastated by today's incident and our hearts go out to our passengers and their families," Taquan said in a statement.
Photo credit John Greim / Contributor / Getty Images