A recidivist burglar died in the early hours of Sunday morning at a property at Volta do Pardal on the Vilamoura estate.
A British couple and their son were woken at around 04:00 and discovered a burglar in their house.
Property owner Trevor Taylor is understood to have pinned down the thief with his son's help while his wife Jill phoned the local police.
The intruder, originally from Cape Verde, who already had valuables and the key to the family jaguar in a holdall and was described by the Taylors as very strong, was tackled by Mr Taylor and his son Scott, and was restrained in a neck-lock by the father.
As officers went to cuff the individual, well known to the courts for his activities, they confirmed he no longer was moving, either uncoscious or already dead.
The British homeowner has not been charged with any crime or offence but is a formal suspect, or 'arguido' as the case involves a death.
The deceased, named today as Paulo Brito, was on remand for burglary offences and, according to his sister, 'had mental health problems.'
Brito also was on parole for burglary and had robbed the house next door to the Taylors' before enetring their property.
Police will wait for the results of an autopsy due in a couple of days before deciding whether any case exists worthy of being passed to the public prosecutor.