Mark Saunders’ father Rodney, a 64-year-old chartered quantity surveyor, said the family was stunned by the news that his son had been killed after a stand-off with police.

"It is an absolute mystery. In some ways it would help if we could find out what went on and why he has done it,” he told a newspaper.

"We are not aware of anything in his work life or private life which might have made him react like this. He has been married about 18 months and they seemed the ideal couple.

"I spoke to his wife this morning at about 2am and my wife also spoke to her. She couldn't throw any more light on the situation. We are just shocked and stunned.

"It is bad enough to have a bereavement in the family but this is exceptional by any standards. You could understand it if he was a terrorist but Mark was not a terrorist."

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