The 32-year-old Hannover stopper was struck by a regional train travelling between Norddeich and Hanover at a railway crossing in Neustadt am Rubenberge and died at the scene.

Police did not reveal the contents of the note.

Enke's agent indicated last night he had committed suicide.

Hundreds of fans gathered outside Hannover's AWD-Arena this morning to sign a book of condolence for Enke, and to leave flowers and scarves and light candles in his memory.

Germany cancelled today's training session following Enke's death.

A statement from the German FA (DFB) released this morning read: "The Germany national team's training planned for this morning has been called off.

"All interview appointments are cancelled."

And tributes to Enke have flooded in from his former clubs.

The keeper started his career at Carl Zeiss Jena and had spells at Borussia Monchengladbach, Benfica, Barcelona, Fenerbahce and Tenerife before joining Hannover in 2004.

Hannover's official website, www.hannover96.de, was this morning dedicated to their former number one.

A statement on an otherwise entirely black home page just read: "We are mourning Robert Enke, 24 August 1977-10 November 2009."

Monchengladbach vice-president Rainer Bonhof, Enke's coach at the club in the 1998/99 season, said on www.borussia.de: "This is shocking news, words fail me."

Carl Zeiss Jena spokesman Andreas Trautmann said: "The right words don't exist for such a tragedy. We are shocked and our thoughts are with Robert's family. They have our heart-felt sympathies."

Jena, now in the German third division, will this morning open a condolence book for Enke which they intend to pass on to his family, it was confirmed on www.fc-carlzeiss-jena.de.

Nuno Gomes, who was a team-mate of Enke's at Benfica, told Benfica TV: "It is a tremendous loss for the world of football. It is very sad news."

Enke spent three years with the Portuguese side between 1999 and 2002.

Barcelona, for whom he only made one Primera Division appearance, held a minute's silence before last night's 5-0 Copa Del Rey win at home to Cultural Leonesa.

Enke, who won eight caps for Germany, was regarded as the favourite to be their number one at the World Cup in South Africa next summer.

Former Germany captain and coach Franz Beckenbauer said on the DFB's official website, www.dfb.de: "I am infinitely sad. When you receive news like this all other problems pale into insignificance."

Hannover president Martin Kind added: "This is an absolute catastrophe, I can't come to terms with it."

Schalke striker Kevin Kuranyi said in the Bild newspaper: "This can and must not be true. Robert was such a great bloke.

"I don't know how I will tell my wife. She is very good friend's with Robert's wife. I feel for his family."

Enke leaves behind his wife, Teresa, and an eight-month-old daughter who the couple had adopted in May.

The Enkes lost their biological daughter Lara in 2006 when she died of a rare heart condition at the age of just two.

Hamburg captain David Jarolim added: "I can hardly breathe because I'm so upset. This is a real tragedy, I can hardly believe it. First his little daughter dies and then this."

"I am stunned. Words fail me," said Chelsea and Germany midfielder Michael Ballack.

A mysterious bacterial infection had forced Enke out of Germany's World Cup qualifier against Azerbaijan in September.

He only recently recovered from the illness and made his return for Hannover in their Bundesliga win over Cologne on October 31.

However, he was omitted from the Germany squad for their upcoming friendly matches against Chile on Saturday and the Ivory Coast next Wednesday.

Germany coach Joachim Low nevertheless insisted Enke was one of the favourites to be his number one in South Africa, saying that the decision to leave him out of his squad was "not a decision against, but rather a decision for Robert".

A decision on whether Saturday's match with Chile will now be postponed is expected today.

A press conference later is expected to answer questions regarding the circumstances of Enke's death.

The German Football League (DFL) have announced a minute's silence will be held at every ground in Germany ahead of the next round of Bundesliga and 2. Bundesliga matches, with all players wearing black armbands.

"We are shocked about the tragic death of Robert Enke," said DFL president Dr Reinhard Rauball.

"He was an excellent sportsman and a special person. We are thinking of his family at this difficult time and wish them lots of strength to cope with this difficult situation as well as possible."

Hannover's director of sport, Jorg Schmadtke, had the unenviable task of informing Enke's team-mates of the tragedy yesterday evening.

"We are deeply affected," he said. "Our sympathy goes out to his family. We have lost an exceptional sportsman and person who has left behind a huge void in Hannover and German football."

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