Tottenham Labour MP Bernie Grant died today at the age of 56, it has been announced.
A statement issued by his office said he died at the Middlesex Hospital in London at 7.30am following a heart attack.
Mr Grant, who had represented his constituency since 1987, was known an outspoken advocate of black and ethnic minority rights.
Prime Minister Tony Blair said: "Although I know Bernie had health problems, his death is a dreadful shock, and my thoughts and prayers are with his family."
Mr Grant, who was a diabetic, had continued to work as an MP in spite of a heart bypass operation and subsequent kidney failure in 1998.
He leaves his wife Sharon - who was also his personal assistant - and three sons.
Mrs Grant said today: "Bernie touched the lives of so many people in a lifetime's work as both a national and local politician, and there will be great sadness today.
"We have lost a great fighter and a champion of justice for oppressed people everywhere. He had a huge heart and I guess that he just wore it out."
Mr Blair said: "He was someone for whom I had immense respect and affection.
"He was a dedicated and diligent constituency MP who worked tirelessly for the less well off, whose commitment to social justice was unwavering and who also made a powerful contribution to development issues.
"He advised me regularly on issues relating to development and on our relations with Caribbean countries.
"He was someone who always made efforts to understand and respect other people's point of view.
"Bernie was also an inspiration to black people throughout the country. One day I hope it will be commonplace to have black and Asian MPs at Westminster.
"When that happens, it will in no small measure be a tribute to Bernie Grant and the inspirational lead he gave."
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