A safety investigation has begun on an aircraft crash in Alaska late on 9 August that included a former senator and the chief executive officer of EADS North America among the passengers.
The National Transportation Safety Board has dispatched a "go team" to investigate the crash 16km (10 miles) northwest of Aleknagik, Alaska.
The agency says local reports indicate that five of the nine people aboard the DeHavilland DHC-3T (N455A) were killed in the accident.
The passengers included former Senator Ted Stevens, an Alaskan Republican, and Sean O'Keefe, CEO of EADS NA and former NASA administrator and Secretary of the Navy during the George W. Bush Administration.
It is not clear if either O'Keefe or Stevens are among the four survivors.
EADS NA released a statement confirming that O'Keefe was aboard the aircraft, noting that "local authorities are reporting that there are survivors and a rescue operation is underway. No other details are available at this time".