A disturbed Queens man was “mentally obsessed” with his 75-year-old retired teacher neighbor and even trashed his car years before he allegedly stabbed the elderly victim to death, friends said.
Dimitrios Manessis, 48, had a bizarre, long-running gripe with George Dourdounas — leading the younger man to blow up in a violent rage on Tuesday afternoon and allegedly slash Dourdounas to death in the Astoria building’s lobby, a neighbor said.
“The guy who killed him, he has issues for no reason in his brain,” one upstairs neighbor told The Post.
“It’s his obsession,” she said. “He’d talk in the streets about George. We walk, he talk about George. I told him, ‘Jimmy, why do you put all your energy on George? Think of something else.’
“I told him, ‘Take George out of your brain,’” she added. “It was a mental obsession.”
Neighbors in the building at 25-75 33rd Street said the accused killer lived in the building with his mother, and has long been fixated with Dourdounas, who was described as a beloved figure among neighbors.
The accused killer for some reason ridiculed the victim’s Greek heritage — even though he is also of Greek descent. He even took a bat to Dourdounas’ car about three years ago.
Shortly after 1:30 p.m. on Tuesday, police and neighbors said Manessis erupted in a deadly attack, slashing the victim’s neck and leaving him dying in the lobby.
Police said EMS pronounced Dourdounas dead at the scene.
Manessis was taken into custody for questioning and charged with murder and illegal weapons possession at the 114th Precinct stationhouse about five hours later.
A photo taken by one tenant showed the accused killer being handcuffed by police inside the building — with his right shoe still splattered with blood.
On Tuesday, a woman stopped by to drop off white carnations at the scene.
“It’s breaking my heart,” said the woman, who asked to be identified only as Diana J. “[Dourdounas] was a humble person. He stood away from people. He wasn’t a person to go back and forth with people. He wouldn’t have an argument with people.
“This is more mind blogging that you would see this with him,” she said. “He’s not confrontational like that. It doesn’t make sense.”