ANCHORAGE, Alaska — Two sightseeing planes that crashed in southeast Alaska collided at about the 3,300-foot (1005-meter) level. That was among the first findings released Tuesday by federal investigators sent to the cruise ship port community of Ketchikan from Washington, D.C., to probe the crash that killed six people and injured 10 Monday. The 14 passengers were all from the same cruise ship, the Royal Princess. Ten were on one plane that had descended from 3,800 feet (1,158 meters) and collided with a smaller plane as both were returning to Ketchikan. The investigation could take months, but the NTSB typically issues a preliminary report within two weeks. Officials said the last two missing passengers were from Canada and Australia. The Coast Guard said two bodies were recovered Tuesday near the crash site of the smaller plane involved in the collision.