A daughter said she was left "in shock" when she found her dad dead on his sofa after burglars ransacked his home.
Mark Smith, 55, died on Tuesday at his house in Grimsby, Lincolnshire, his daughter Katie said.
It is believed that either before or after his death, two men entered his home and stole a number of personal possessions - including Christmas presents for his grandchildren, his phone, money and some kitchen items.
Following the death of Mr Smith and the burglary at his home, Humberside Police launched an investigation, Grimsby Live reports.
Katie said she saw her dad on Monday evening and even though he was poorly, she would have never expected him to die the following day.
She explained; "He had the odd heart condition throughout his life, but never anything too bad. When the coroner rang his doctors to inform them of his passing, even they were shocked he'd died.
"I went back to his house at 10am on Tuesday and found him dead on the sofa. The worst part was I had my children waiting outside in the car.
"I would never have expected to walk into that and I made sure to keep the kids away as it's really not a nice sight for them."
She said: "It was a complete shock when I first saw the scene, as soon as I found him though I phoned the paramedics.
"However, things got worse when I started to look around, I noticed something wasn't quite right.
"His head had moved and his phone had disappeared. When I rang it, it wasn't in his flat, the paramedics then asked me to look around to see if anything else was missing.
"His laptop was no longer on the table, £2,000 had gone from an envelope, his new drill and circular saw had disappeared, my children's Nintendo Switches weren't there and some Christmas presents he'd bought for them had been taken too.
"As well as these valuable items, they also took some random things like a frying pan from the kitchen, my dad's cigarettes, and some fresh orange juice out the fridge."
Katie's aunt, who lives across the road, said she saw two men leave Mark's house in the early hours of the morning.
The heartbroken daughter said: "At the minute, we've got so many questions going around our heads. If I'd had gone to his earlier that day, as planned, could I have stopped all this?
"We're not bothered about retrieving the stuff, it's more the principle than anything else now.
"My biggest fear is for others. If they're capable of doing all this when someone is possibly dead, what are they capable of doing when someone is alive?"
Humberside Police said in a statement: "On Tuesday 26 October 2021, officers attended to a property on Park St in Cleethorpes at 10am.
"On arrival at the address, a man was found to have sadly died.
"The circumstances surrounding his death are not being treated as suspicious and our thoughts are with his family at this sad time.
"We have also received a report of a burglary at the same property, the two incidents aren’t thought to be linked.
"Extensive enquiries are ongoing."
