BERLIN One March day in the last weeks of World War Two, more than 70 German children squeezed into a plane designed for 14 hoping to be flown to safety from the advancing Soviet tanks in north-eastern Nazi Germany.
Minutes after takeoff the plane dived into an icy lake, killing everyone on board. Nearly 70 years later, former war foes Germany and Poland are joining forces to try to raise the wreck from Resko Przymorskie in western Poland.
"The idea that whenever I went to the lake, I was walking by an open grave with so many children made me uneasy. To me, what we are doing is a natural thing," Zdzislaw Matusewicz, mayor of the Polish town of Trzebiatow, told Reuters.
"Children are innocent in war -- that applies to German as well as Polish children."
The Polish mayor is working with Germany's War Graves Commission to retrieve the remains of the mostly unidentified children and four crew from what is known in German as Kamper See and bury them in a nearby war cemetery.
Barely any of the childrens' identities are known but since the project began, some people have come forward, hoping to obtain details about family members who went missing without trace in the chaotic last months of the war.
The water in the lake, close to the Baltic Sea, may have dissolved the bodies but some experts say that mud may have protected the plane and some DNA evidence could be intact.
"This is a very big project. It is technically difficult and a real challenge," said Wolfram Althoff, the Grave Commission's special representative for the project.
Both sides say the project is an important symbol of how far Poles and Germans have come in putting behind them a Nazi occupation which left 6 million Poles dead, many of them in mass civilian executions or extermination camps such as Auschwitz.
Schools on both sides of the border are raising funds to help foot a bill for raising the wreck which officials say could reach as much as 150,000 euros, if it proves possible at all.
On March 5, a group of German school children took part in an anniversary ceremony on the lakeside and schools have also launched an appeal for possible relatives of the victims to come forward.
"It is a one-off, nothing like it has happened before. The fact that a Polish mayor initiated this makes it a project that should be supported," Althoff said.
The end of Communism has allowed the German War Graves Commission to re-intern hundreds of thousands of war dead from eastern Europe in the last two decades.
The neighbors have been drawn closer together by Poland's accession to the European Union and strong economic ties which have seen tens of thousands find work in Germany.
Tensions still flare sometimes, however, particularly over a group lobbying for the rights of Germans expelled from territory which became Polish after the war, who wield considerable influence in Chancellor Angela Merkel's conservative bloc.
The head of Germany's Arnold Zweig Europe School in Pasewalk said attending an anniversary ceremony at the lakeside last month was a live lesson in German-Polish history for his pupils.
"We wanted children involved because they are the people who have least to do with war," said headmaster Norbert Haack. "We want to show that we Germans stand together with Poles, although - and we made this clear - the war was started by Germans."
Germany evacuated hundreds of thousands of civilians, many of them children put in refugee camps, westwards from the area around the wreck in early 1945 in hurried efforts to save lives from Red Army soldiers taking revenge for SS atrocities.
It is unclear if a Soviet tank brought down the plane or if it crashed simply because it was so overloaded.
The Dornier 24 plane was a flying boat, designed to rescue shipwrecked people but by the end of the war, Germany used it to transport refugees, including many from the area around what is today's German-Polish border, said Althoff.
"The pilots flying the planes knew they were too heavy. Each time they took off, they hoped they'd make it," he said.
Only about two months before the tragedy at the lake, a Soviet submarine sank Germany's Wilhelm Gustloff ship in the Baltic Sea, killing around 9,000 civilian evacuees, six times as many as the number that drowned on the Titanic.
Until 2001, any investigation at the lake was impossible as the area was a closed Polish military zone. Divers in 2009 found debris in the marshy lake and specialist photography has shown the wreckage is strewn across a large area.
Researchers at a local paper have revealed one mother died with five daughters on the plane and investigators hope possible relatives will get in touch when they hear of the project.
A small black shoe and a piece of wreckage of the plane in a local museum are the only material reminders of the tragedy.
"It was very sad. We wanted to think about the children and their fate and we want to bring Germany and Poland closer together," said 15-year-old Dominik Wollenzien, a pupil who attended the ceremony in March.
(Reporting By Madeline Chambers; editing by Patrick Graham)