The stunned roommate of the nut who allegedly attacked two Upper West Side victims said Friday that the man calmly told him he was just going for a walk in the park before the violence — as cops searched their home for evidence of a possible hate crime and carted off items including a Koran and book on Cuban revolutionary Che Guevara.

The roomie recounted his seemingly blase encounter with now-suspected ex-con Raul Morales, 51, to NYPD investigators in Spanish at their apartment on Amsterdam Avenue near West 88th Street in Manhattan.

The roommate said Morales — a former drug parolee and an apparent onetime Brooklyn security guard — did not appear angry or agitated, leaving him shocked at what cops said was to come. 

Raul Morales is suspected in the stabbing. NY Post

Investigators carted off items including a Koran and book on Cuban revolutionary Che Guevara. Jordan Donegan / NYPost

Neighbors at the building, which is near Central Park, also said they had no inkling Morales could allegedly pull off such violence.

“Never displayed anything,’’ said a resident who only identified himself as Tony J, 54.

“That’s why when I seen him yesterday coming out the building in handcuffs, I was like, ‘What the f–k is he locked up for?” he said of Morales.

“It blew my mind.

“He was always nice. he’s like, never no problem,’’ said Tony, adding he’d seen Morales at the building for years. “He was never a head case, and he didn’t display no mental problems or nothing like that.

“Every time I see him, he was always, ‘Hey, how you doing?’ Super, super cordial. … That’s why if he had a mental break, I have not the slightest idea.

Moshe Yezhak Grunhaus was stabbed in the attack. Facebook / Lidia Lander

“But you never know what goes through people’s minds. It’s New York City for you.”

Another building resident, Carlos Ramos, 73, said he’d seen Morales around on and off for a few years and only really knew he went outside more in the summer — but was equally shocked at the notion that his neighbor was Thursday’s attacker.

Morales is believed to have yelled, “Allahu Akbar!,’’ or “God is greater!’’ in Arabic during the separate screwdriver and knife attacks on a Jewish New Yorker in a yarmulke and an Asian man.

“I don’t think he knows what it means to be racist” because “there are a lot of Jewish communities here,’’ Ramos said.

“Let me tell you. The Jewish people that live around here? They mind their own business,’’ he said.

As for Morales, “he was a lonely person all the time. Lonely. I see him alone.”

The neighbors spoke as cops were executing a search warrant on Morales’ apartment in the building, where he was dragged out of after Thursday’s assault.

He was custody but had yet to be charged as authorities pushed to gather more evidence from the warrant — as well as scour for video footage of the attacks — to try to bolster the charges they are sure to bring against him even with his possible mental illness, including involving the potential hate crime, law-enforcement sources said.

Members of the New York City Police Department Crime Scene Unit collect evidence at the scene of a stabbing near West 84th Street and Central Park West in Manhattan, New York. James Keivom for NY Post

Among the items they hauled off Friday was a Koran and the famous 1997 biography, “Che Guevara: A Revolutionary Life” by The New Yorker writer Jon Lee Anderson.

Morales — who apparently worked as a security guard in Brooklyn at least around 2007, previously did two years in state prison on drug charges in the early 1990s and remained on probation for much of the decade, sources said.

He had at least two drug-possession arrests under his belt. He also has five prior sealed arrests, sources said.