Two men were being questioned by the RUC yesterday following the death of an archaeologist and writer, Mr Laurence Flanagan (68), after a robbery in his home in the Ormeau Road area.
Police officers discovered his body at the bottom of the stairs after neighbours raised the alarm. He had face and head injuries. He had been tied up, and credit cards had been stolen.
Dublin-born Mr Flanagan, who was twice widowed and the father of three daughters, was a former keeper of antiquities at the Ulster Museum where he worked for almost 40 years.
Chief Insp Alan Mains asked locals to look around their homes for the credit cards and to come forward if men had offered gardening services recently.
Mr Flanagan organised an exhibition to mark the 400th anniversary of the Spanish Armada, one of the most successful ever displayed there, before retiring in 1988. He wrote numerous books including Ancient Ireland, Life Before the Celts, Irish Wrecks and the Spanish Armada, Directory of Irish Archaeology and A Chronicle of Irish Saints.
A Dublin archaeologist, Dr Peter Harbison, said yesterday Mr Flanagan had been the leading expert in Early Bronze Age axes in the 1960s and had excavated two megalithic tombs in Co Donegal.
His first wife, Deirdre, who died in 1984, was a leading expert in Irish place names and lectured at Queen's University.
The SDLP Assembly member for South Belfast, Ms Carmel Hanna, deplored the killing and said the elderly were seen as "easy targets by thugs who roam our streets".