Det Supt Terry Mann on the steps outside the Sheffield club where Joshua Green was stabbed to death in the early hours of New Year's Day.He made a fresh appeal for information despite already speaking to many of the people in the club that night.
"While many people have provided us with statements others have chosen to stay silent or have refused to help."
Four people are answering bail in relation to the killing but no-one has been charged.
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Most escaping a frost overnight with cloudier skies and patchy rain. Turning colder on Monday stronger northerly winds, rain and hill snow.
By the end of Monday a cold northerly wind, widespread frost and risk of wintry showers
Flying Scotsman travelled alongside three modern trains to celebrate the "past, present and future" of Britain's railway this morning.