Labour leader Sir Keir Starmer leads tributes, saying Mr Mitchell served “with remarkable commitment”.
The former MP Austin Mitchell has died at the age of 86, the Labour Party has confirmed.
He worked as a journalist for Yorkshire Television before being elected to the Great Grimsby constituency in 1977. He held the seat until 2015.
Mr Mitchell served as opposition whip and shadow spokesperson at the Department of Trade in the 1980s.
Labour leader Sir Keir Starmer said Mr Mitchell had served the voters “with remarkable commitment for 38 years”.
Mr Mitchell was a colourful figure in the North East Lincolnshire port, even temporarily changing his name by deed poll to Austin Haddock in 2002 in a bid to promote the fishing industry.
“There are few MPs whose dedication to their constituents would translate into changing their surname to ‘Haddock’ to promote local industry”, said Sir Keir.
“His big sense of humour was matched by his deep Labour values. My thoughts are with his wife Linda and his children.”
Conservative MP Michael Fabricant tweeted that Mr Mitchell was a “super guy”.
He added: “A former broadcaster, who often made his independent minded views known. He and I got on well in the House of Commons.”
Mr Mitchell was born in Bradford in 1934 and moved to New Zealand in the late 1950s to lecture at the University of Otago. He returned to the UK in the late 1960s.
He was a TV journalist for the nightly Calendar news programme between 1969 and 1977, apart from a brief spell at the BBC in 1972.
Former Labour MP Melanie Onn, who was elected to the Great Grimsby seat after Mr Mitchell stood down in 2015, said he would be “greatly missed by many” and described him as a “tireless champion of the people and town of Grimsby”.
She added: “On a personal level, Austin was unfailingly supportive to me as a new MP, still a bruising advocate of the Labour Party and gave his time, advice and expertise generously.”
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