No one was believed to have survived the crash of a small plane that was carrying a six-member organ transplant team and their cargo of donor organs, authorities said Tuesday.

Searchers found human remains during a search in Lake Michigan, about six miles northeast of Milwaukee, a Coast Guard official said Tuesday.

The team's lifesaving mission — carrying unspecified organs from Milwaukee for transplant to a patient in Michigan — was cut short Monday when the Cessna Citation went down in 57-degree water shortly after the pilot signaled an emergency.

Those on board were two surgeons and two donor specialists from the University of Michigan Health System and two pilots who regularly fly their transplant missions.

"The condition of the aircraft debris and human remains found indicate a high-speed impact," said Coast Guard Capt. Bruce Jones at a news conference. "We believe this to have been a non-survivable crash."

Dr. Darrell A. Campbell, chief of staff of the University of Michigan Hospitals and Health Centers, said the thoughts of the university community were with the families of those involved.

"We take consolation in the fact that the team was on a mission to help another," he said.

The patient who was to have received the transplant organs was in critical condition, the university said. Jay Campbell, executive director of the Wisconsin Donor Network, declined to say which hospital the team was working with, citing privacy regulations.

The first human remains were found late Monday but hadn't been identified, Jones said. Divers stopped searching at nightfall, while crews of a Coast Guard boat and helicopter continued searching using night vision goggles

Only small parts of the plane had been found so far, Jones said.

Jones said they wouldn't speculate on the crash's cause. The National Transportation Board was expected to arrive later Tuesday.

The university identified those aboard the plane as: Dr. Martinus "Martin" Spoor, a cardiac surgeon who had been on the faculty since 2003; Dr. David Ashburn, a physician-in-training in pediatric cardiothoracic surgery; Richard Chenault II, a transplant donation specialist with the university transplant program; Richard Lapensee, a transplant donation specialist with the university transplant program; and pilots Dennis Hoyes and Bill Serra.

The plane took off from General Mitchell International Airport in Milwaukee and was headed for Willow Run airport near Detroit, a 42-minute flight, Federal Aviation Administration spokesman Tony Molinaro said.

Within five minutes of its takeoff, the pilot declared an emergency and requested a return to Mitchell, Molinaro said. But the plane dropped off radar screens just after the pilot made that request and the Coast Guard was contacted.

Light rain was falling at the airport with wind of 12 mph, gusting to 22 mph, according to J.J. Wood, a National Weather Service meteorologist.

The plane was leased by the University of Michigan Health System in Ann Arbor, according to the university. It's owned by Toy Air and based at Willow Run Airport in Ypsilanti, Mich.

Jones estimated the plane was going 185 to 190 mph. He said people could survive for 16 hours in 57-degree water.