Investigations are continuing into the fatal crash of a Cessna Citation Bravo business jet ealier this week.
The aircraft, carrying a six-member organ transplant team and a cargo of donor organs, crashed into Lake Michigan about 10km (5.4nm) north-east of Milwaukee shortly after the pilot signalled an emergency.
According to the US Coast Guard, "the condition of the aircraft debris and human remains found indicate a high-speed impact".
The US Federal Aviation Administration says the Citation took off from General Mitchell International airport in Milwaukee at 16:00 local time on June 4 and was bound for Willow Run airport near Detroit - a 42min flight.
"Within five minutes of its departure the pilot declared an emergency and requested a return to Mitchell, but at that time the plane was no longer on our radar screens," the FAA says.
The aircraft was owned by Southfield, Michigan-based Toy Air.