A pensioner from Royston said he was scared for his life after a 17-year-old intruder broke into his home on Sunday morning.

Following a night of broken sleep, Tom Johnston – who has chronic health problems – had finally nodded off in a chair in his living room when he woke to find a teenager in his Princes Mews flat just after 6am.

The 67-year-old, who walks with mobility aids, had just come out of hospital with a serious heart complaint.

“I thought I was back in the hospital,” said the former locksmith.

“I thought it was the drugs and I was hallucinating, I couldn’t believe there was someone in my flat behind the curtain.

“I asked him what he thought he was doing, and he kept saying ‘we’re mates, we’re mates, we know each other, you invited me round here’.

“I told him we weren’t mates, I didn’t know him.

“I got my stick and I threatened to hurt him because I didn’t want him to think he could just take anything or hurt me.”

The teenager moved from behind the curtain into a corner, and Mr Johnston noticed he didn’t have any shoes on.

“He had climbed over a fence and through a window to get in, he damaged the window and my mobility scooter,” he said.

“He said he had mates outside, a group of them.”

Mr Johnston pulled the red cord in his sheltered housing scheme accommodation which alerted staff and used his phone to called the police.

He told the Crow: “I said ‘I’ve got him, I’ve caught a burglar in my home’. It was a three-way conversation, with staff on the intercom, and with the police.

“The police said they would be a while as they were coming from Stevenage. I was terrified he was going to take a knife out his pocket or something and kill me.

“I told the police to come in the back way, but they went to the front and buzzed all the flats waking up all the elderly and disabled people who live here – it was pandemonium.”

Police arrested the intruder and took him into custody. Det Sgt Alex Willcox, from the North Herts Local Crime Unit, said: “Understandably this was extremely distressing incident for the resident, however the subsequent thorough investigation found insufficient evidence that the suspect had broken into the property with the intention of committing a burglary.

“It is currently believed that he made a genuine mistake in entering the building after consuming a large amount of alcohol to the point he was no longer in control of his actions.

“He has been released with no further action to be taken in respect of the alleged burglary offence, however he has been given strong words of advice and we are currently looking into whether any other offences have occurred.”

Mr Johnston added: “I think it’s appalling how this has been treated.

“They say he didn’t know what he was doing, but he took his shoes off and climbed over a six-foot fence! You can’t just plead ignorance. I used to be a locksmith and safe engineer, I know what stress this kind of crime does to people.”