Former RTE DJ Gareth O'Callaghan has blasted Dublin saying it is now a "sad drug-infested kip" that is unrecognisable from his youth.
The popular broadcaster and author, who now lives in Cork, was visiting his home city for medical treatment.
O'Callaghan is currently battling Multiple System Atrophy, an incurable neurodegenerative disorder.
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And the mental health campaigner took to social media to say how shocked by how dangerous it felt walking around the city.
Writing on Twitter on Tuesday evening, he said: "Dublin city centre is finished. It's a sad drug-infested kip now. I've just left our B&B to get food.
"Was in town for medical tests today. The city centre has been reduced to a complete shithole at night.
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"It's dangerous like I've never known. Just spoke to a garda who agreed."
The veteran DJ went into further detail in a lengthy Facebook post, saying the capital was unrecognisable from his youth.
He said: "There's still a handful of great pubs where you can enjoy a pint (albeit in some places at exhorbitant prices - €5.90 for a pint of stout ffs in one place we called into! So I don't go to too many of them lately.)
"But the city is now becoming more sinister and more nasty than I've ever known it to be in the past.
"Sadly this city I once loved is now controlled by gangs. It wasn't how I knew it to be years ago, as I walked back to where we were staying tonight with some food from a local takeaway.
"Even a young garda asked me if I knew exactly where I was going.
"I agreed with him when he described the city centre as an incurable kip.
"He looked no more than twenty. When I was twenty, this city was a great place."
Despite the criticism, O'Callaghan said he had a "great evening" during his stay in the city.
His comments caused huge reaction online, with some agreeing with him and others defending their home city.
Laura O'Leary said: "I moved back to Dublin last year after being in London 7years.
"I have to agree with you, it’s so sad seeing how many people are roaming around out of it or that are homeless.
"Everyday I walk home from work there are people begging me for money.
"It’s such a divided society here. People live in a bubble here. I never seen such extremes before, it’s so scary."
But Kevin McGahern disagreed, saying: "Over 10 years living in Dublin. The closest I came to trouble was a young lad on coke who threatened to fight me if I didn't give him one of my fags. I refused.
"It got tense until he spotted his mother looking out the window. He them asked if I'd pretend to be his friend."
