Do17 Crash landing Aug 1940 Norfolk UK

Hi everyone this is my first posting here.
My uncle and I are trying to find out more information regarding a Do17 that was brought down over Norwich, Norfolk towards the end of August 1940.

The crew were unhurt and the virually in-tact plane was put on show to the public in Eaton Park, Norwich, as recorded by the Eastern daily Press on 31st August 1940. The problem is we can't find any reference to this incident in any other books or records. I work with a chap who as a boy of 10 years saw it come down. He and his friend watched from the bushes as they thgough the Germans had landed specifically to take them prisoner, the crew however just lit up cigarettes and calmly waited to be taken prisoner after their attempts to destroy their a/c failed.

Amore information on this incident would be appreciated.

Regards

Clive