The four occupants of the aircraft are all presumed dead.
ADVERTISEMENTHuman remains and debris have been found in the Baltic Sea during a search operation to find a missing private jet.
The Cessna Citation 551 was last recorded off the coast of Latvia on Sunday before it crashed in mysterious circumstances.
The four occupants of the aircraft -- including a prominent German businessman -- are believed to have died.
Latvian coast guard vessels and underwater robots have been surveying the area, northwest of the port city of Ventspils, since Monday.
"[We found] remains of human bodies we believe to be associated with the crash," Lt. Cmdr. Peteris Subbota, head of the Latvian military’s Marine Search and Rescue Coordination Centre told The Associated Press.
The underwater search has not yet located the plane wreck.
Air traffic controllers lost contact with the Austrian-registered Cessna plane shortly after it took off from the Spanish city of Jerez de la Frontera, on its way to Cologne.
Several European countries scrambled fighter jets as the plane flew around 3,500 kilometres across Europe but they were unable to see or contact anyone in the cockpit.
The aircraft had earlier reported problems with cabin pressure.
Latvian authorities are hopeful that they will find the plane wreckage, as the water at the crash site is only 60 metres deep.
The Swedish coastguard has also sent rescue planes, boats and a helicopter to the Baltic Sea to assist the salvage operation.