‘Closing down forever’: Last German message intercepted by Bletchley Park code breakers revealed by GCHQ

German air force personnel recorded signing off before surrendering to Allied forces

Code breakers at Bletchley Park continued intercepting Germany military communications until the very last days of the war (GCHQ)

The very last German military message intercepted by Bletchley Park code breakers has been published for the first time.

GCHQ, the successor of the Bletchley Park team, revealed the final intercept to mark the 75^th anniversary of the end of the Second World War in Europe on Friday.

Although it had been clear for some time the wear was nearing an end, the UK continued monitoring German communications until the very end to ensure there would be no final stand by the defeated Nazi forces.

On 7 May 1945, one day before Germany’s final surrender, the last vestiges of one air force signals network monitored at Bletchley Park had retreated to the small seaside town of Cuxhaven, near Hamburg, on Germany’s North Sea coast.

As the Allied forces closed in, a last statement was broadcast at 7.35am and picked up almost 500 miles away by code breakers working in the grounds of their Buckinghamshire country manor house.

“British troops entered Cuxhaven at 1400 on 6 May – from now on all radio traffic will cease – wishing you all the best. Lt Kunkel,” it read.

Soon after a second message was sent: “Closing down for ever – all the best – goodbye.”

GCHQ historian Tony Comer said the transcripts provide "a small insight into the real people behind the machinery of war".

He added: “While most of the UK was preparing to celebrate the war ending, and the last of the German military communicators surrendered, Bletchley staff – like today's GCHQ workers – carried on working to help keep the country safe.”

The network which GCHQ analysts had broken into was nicknamed the “Brown Network” and at its height in 1944 spanned from the Baltic coast all the way down to Vienna.

It was used by the Nazis to co-ordinate experimental new weaponry they were developing even in the dying days of the war.

The Brown Network was particularly involved in electronics, helping develop new methods of guiding bombers towards their targets during the Blitz and, later, the V1 flying bombs and V2 missiles.

It was using its own dedicated cryptographic key through the famous Enigma machines, which Germany used to encode its communications, but Bletchley Park had managed to break this in 1940 and could eavesdrop in on what the Brown Network's operators were saying to each other.

By May 1945 the network had shrunk to a remnant in Denmark and Germany’s North Sea coast, and when stations did send out messages almost nobody was answering. Mr Cromer said some of these final intercepts showed the operators asking if anyone had any cigarettes left.

On 7 May only one station was left, in Cuxhaven, and one day before the end of the war in Europe it sent out one last, final message before closing down and surrendering to the nearby British forces. The war would be over just 24 hours later.