The violent Bronx nut accused of randomly stabbing a 14-year-old boy to death as he walked to school was booted from court Sunday after a “crazy’’ rant about the White House, al-Qaeda and Satan.

The disturbing outburst came as video surfaced of the suspect wildly stabbing one of his neighbor’s Ring doorbell cameras with a huge blade in November.

Waldo Mejia, 29, had been hauled before the judge for allegedly killing teen Caleb Rios by sticking a knife into the boy’s chest on East 138th Street on Friday morning. The suspect was also being arraigned on an unrelated stabbing Mejia allegedly committed about a week ago.

But the hearing turned into chaos when the alleged killer at one point screamed he was “with Satan.

“My name is Waldo Mejia, so get ready to f–king suffer along with me!” he shouted, according to the Daily News.

When a court officer grabbed his cuffs, he turned to her and said, “Let me go. Let me go. I’mma catch you when I can.

“I’m with Satan!” he screamed. “Piece of s–t a–people! Get ready to f–king suffer!”

Authorities had charged Mejia — who lives down the block from the teen’s family and right across from the 40th Precinct — with second-degree murder, attempted murder and other offenses for the heinous crimes.

He also has a lengthy rap sheet and a long history of mental illness.

“He started yelling ‘White House!’ and ‘al-Qaeda!’ ” a court officer told The Post, describing Mejia’s other antics during the hearing. “He’s back there yappin’ now. He’s just nuts — you can look at his face and see it.”

Mejia’s lawyer, Paul Horowitz, said the court remanded his client and ordered a psychiatric exam.

“I will not be defending him in the future,” Horowitz said. “I was just here for the arraignment. … He acted out. He was just screaming nonsense!”

Caleb Rios was walking to school near Lincoln Avenue and 138th Street around 9 a.m. when Mejia allegedly launched his gruesome attack that prompted NYPD Commissioner Jessica Tisch to say the state’s legal system “continue[s] to fail us.”

As Caleb lay dying from the wounds, he made a heartbreaking last phone call to his dad, prosecutors said.

“He called his father and told his father that he couldn’t breathe and that he was scared, and his father heard him dying,” Bronx District Attorney Darcel Clark told reporters at a Saturday news conference. “It’s unfathomable to think about the level of this tragedy.”

Authorities rushed the boy to Lincoln Medical Center, but he died from his injuries.

“Today, a 14-year old-boy is dead,” Tisch said at the time. “A family is devastated, a city is in mourning, and the systems that we have in place to deal with repeat offenders and individuals with severe mental health issues continue to fail us.”

Rios’ family declined to speak to The Post on Sunday, with a young man telling a reporter through a closed apartment door that his family “wants to keep it private.”

Mejia has also been charged with attempted murder for allegedly stabbing another man near Alexander Avenue and the 138th Street Station in Mott Haven in the borough at about 3:50 a.m. on Jan. 5, according to a criminal complaint.

During the attack, Mejia allegedly stuck his 38-year-old victim with “sufficient force to cause the knife to fully perforate through said person’s left arm and enter into said person’s chest cavity, causing a laceration to the artery of his left arm, a significant loss of blood and loss of consciousness requiring life-saving surgery at a local Bronx hospital,” the complaint said.

That encounter also earned Mejia a pair of assault charges, court docs show.

The suspect has had at least four more prior criminal cases — including a May 2017 arrest in which cops caught him with a loaded 9mm pistol and an April 2019 arson charge for setting the lobby of his ex-girlfriend’s building on fire, authorities said.

He later pleaded the arson charges down to reckless endangerment and was granted a conditional discharge, officials said.

Mejia was well-known for terrorizing his neighbors and even stabbed one of their Ring doorbell cameras with a huge blade back in November.

The resident who lives in the apartment declined to give his name to The Post on Sunday but was happy to hear his off-kilter neighbor — who also tried to kick his door in — is now in custody.

“I’ve been really scared for lots of days in a row,” the man said. “When they grabbed him and then when he did what he did to my camera and then three days later he was in the building? I got mad scared.

“We all knew what happened to the kid could have happened to me,” he said of Caleb. “Could have happened to my wife. Could have happened to my mother.”

A young couple who lives directly below the alleged killer described Mejia as “f–king insane.

“We’re all terrified of him,” the second man said. “Every night at like 4 or 5 a.m. you’d hear him stomping around the apartment yelling, ‘Leave me the f*** alone!’

“And if I’d see him down in the morning … you could tell he was up all night,” he continued. “I’d nod to him, and he just looked at me with the same scary face he had on when he was stabbing that camera.

“We all knew he was mentally ill, but we didn’t think he was going to do this.”