A 102-year-old man fought off an intruder who tried to force his way into his home.
John suffered cuts and extensive bruising trying to stop the man, who tried to get into the property in Lincoln on Tuesday by claiming he needed to check the lights.
"I thought that sounds a bit dodgy," said the centenarian.
He and his wife Joan, 97, said they were very shaken up by the incident. Police have appealed for information.
It is the second attack at their home in six months and the couple said they wanted to publicise what happened to warn others about the risks of answering the door to strangers.
'Blood all over'
John said he knew something was wrong when the man told him why he was there.
"By that time he had pushed the door wide open and stepped in, and I said 'you're not going to come in here mate'."
"He gave me a few clouts - I was hoping to give him a few back, and he ran away. He must have been frightened."
The couple's daughter, Jill, said: "The man damaged my dad's arm really badly. There was blood all over.
"My dad was really shook up and it's upset my mum. This is the second time it has happened in six months.
"Give him his due, for his age, he did have a go back."
In a previous incident, the couple let a man into the house who had claimed to be a gas engineer. A handbag and purse were stolen.
"We are used to going to the door and opening it, but you can't now," Joan said.
Lincolnshire Police said they were investigating the latest attack, and another nearby on the same day where cash was stolen from a woman in her 90s.
Ch Insp Phil Baker said: "These two incidents are clearly concerning because they involve elderly and vulnerable victims.
"In both incidents the offender has used force to push past the occupants and, in one case, stolen cash."
He said anyone with information should contact the force.