Anchorage, Alaska • Two sightseeing planes carrying cruise ship passengers in Alaska collided at about the 3,300-foot level before they crashed, the National Transportation Safety Board announced after a team arrived from Washington, D.C., to investigate the crash.

The two planes collided in mid-air Monday, and the Coast Guard raised the death toll to six people on Tuesday after finding the bodies of two people who had been missing. Five of the dead, including a man from Utah, were passengers and the sixth was the pilot of one of the planes.

Federal investigators said the larger plane, a de Havilland Otter DHC-3 with 10 passengers and its pilot, had descended from 3,800 feet and collided with a smaller de Havilland DHC-2 Beaver, carrying four passengers from the same cruise ship, the Royal Princess, and the pilot.

The federal investigation into the cause of the crash could take months, but a preliminary report is expected to be released within two weeks, said Peter Knudson, a spokesman for the NTSB.

(Dustin Safranek/Ketchikan Daily News via AP) Two U.S. Coast Guard 45-foot response boats drift through George Inlet as part of a search effort on Tuesday, May 14, 2019, near Ketchikan, Alaska, at the site of a collision between two float planes. Dive teams plunged into the icy cold waters of the southeast Alaska inlet Tuesday, searching an area the size of 24 football fields for two cruise ship passengers missing after two sightseeing planes collided.

Coast Guard Lt. Brian Dykens said Tuesday evening that his agency and the Ketchikan Volunteer Rescue Squad found the two bodies of those who were missing near the crash site of the smaller plane involved in the collision, a single-engine de Havilland DHC-2 Beaver.

The planes came down about a mile and a half apart, with some of the debris falling on land near George Inlet, about 8 miles from the cruise ship port of Ketchikan.

The Beaver, the smaller plane, appears to have broken apart in midair, according to Jerry Kiffer, duty incident commander of the Ketchikan Volunteer Rescue Squad. He said the plane’s tail and section of the fuselage were 900 feet from the aircraft’s floats, which landed near shore.

The smaller plane was partially submerged in the shore of George Inlet after the single-engine plane overturned and hit some trees before crashing, according to Coast Guard Lt. Brian Dykens. The larger Otter landed in water and sank, he said.

One passenger on the larger plane died, as did two passengers and the pilot on the smaller plane, Princess Cruises said in a statement.

Alaska State Troopers in a statement late Tuesday identified the passengers who died as 46-year-old Louis Botha of San Diego, 56-year-old Simon Brodie from Temple, New South Wales, Australia, 62-year-old Cassandra Webb from St. Louis, 39-year-old Ryan Wilk from Utah and 37-year-old Elsa Wilk of Richmond, British Columbia, Canada. Also killed was the pilot of one of the planes, 46-year-old Randy Sullivan of Ketchikan.

The larger plane was operated by Taquan Air of Ketchikan and passengers booked the flights through the cruise ship as an excursion. The other plane was operated by Mountain Air Service of Ketchikan, and the four booked the flight independent of the cruise ship, Princess Cruises said.

After the crash, the 10 injured people were initially taken to a hospital in Ketchikan. Four patients with broken bones were later transferred to Harborview Medical Center in Seattle, spokeswoman Susan Gregg said.

Three survivors were released from PeaceHealth Ketchikan Medical Center in Ketchikan on Tuesday. Hospital spokeswoman Marty West says the remaining three are in fair condition.

The Royal Princess left Vancouver, British Columbia, on May 11 and was scheduled to arrive in Anchorage on Saturday.

Associated Press writers Martha Bellisle in Seattle, Rob Gillies in Toronto and Michelle A. Monroe in Phoenix contributed to this report.