It is understood the Ikaroa Rawhiti MP had been unwell for some time, and family members had travelled from overseas to be with him, and close colleagues were also visiting.
Neither the family nor the Labour Party would give the reason for his ill-health. Mr Horomia had struggled with his weight and previously revealed he was a chronic asthmatic and had an enlarged heart.
Mr Horomia was at Parliament a fortnight ago where he took part in a powhiri for a group of visiting Pacific Island Parliamentarians and spoke on the Waitaha Claims Settlement Bill. He also travelled down for drinks hosted by Labour MP Shane Jones last month to celebrate his return to the front bench.
However, he has struggled with his health since the last election. He usually led the Labour contingent onto the marae at Waitangi but was not there this year. He was also absent at Ratana Anniversary celebrations, which he said was because he was attending a tangi.
Mr Horomia was first elected as the MP for Ikaroa Rawhiti in 1999 and is regarded as Labour's `kaumatua' in Parliament, respected for his widespread links to Maoridom. He was Minister for Maori Affairs between 2002 and 2008.
Mr Horomia was born in Tolaga Bay and was raised in an extended whanau with particular guidance from his grandmother.
He was educated at the Mangatuna Native School and Tolaga Bay Area School and said it was during his schooling he got his first taste of racial division; he and other Maori children walked 5km a day to school and were passed every day by an empty school bus picking up Pakeha children.
"I used to dream of being picked up by that school bus but, as I grew older, we became more resilient. We went from wishing it would stop to pick us up to thinking that if it did we wouldn't hop on anyway,'' he said in his maiden speech to Parliament.
"I relate that story now because Maori are often told we've missed the bus. In many cases Maori have not even had the opportunity to get on the bus.''
Mr Horomia had a varied career after leaving school; labourer, fencer and scrub cutter, printer, shearer and forestry contractor.
In 1982 he oversaw Labour Department work schemes in the East Coast, Poverty Bay and Hawke's Bay regions before working as a Group Employment Liaison Scheme field officer in the mid `80s.
From there he moved into the department's corporate office and management positions with the liaison scheme. He continued rising through the ranks, eventually becoming general manager of the department's community employment group.
He stayed with the department until entering Parliament in 1999 after winning the Ikaroa-Rawhiti seat and was made Associate Minister of Maori Affairs and Education.
Less than a year later he rocketed up the ranks to Maori Affairs Minister when incumbent Dover Samuels was sacked.
Roles outside work included chairing Ngati Porou, the Te Kohanga Reo Trust Training Board and the Hatea Rangi Maori Council, being a Maori warden and a member of the Youth Advisory Board, the New Zealand Lotteries Board and several Maori organisations.
Mr Horomia represented the East Coast in rugby and remained a keen supporter. He played in the parliamentary rugby team into his 50s.
In his younger days he also participated in many other sports, including boxing, while his interests included gardening, travelling and listening to jazz and blues.
Of Ngati Kahungunu, Ngati Porou, Ngai Tahu and Te Aitanga Hauiti descent, Mr Horomia married Gladwyn and they had three sons - Desmond, Wallace and Turei.
Mrs Horomia died of cancer in 1993.
- APNZ / NZ Herald staff