THE deranged supporters of accused CEO assassin Luigi Mangione are at each other’s throats fighting for his attention as one mystery fan managed to sneak a love note into his prison cell.

Ivy League aristocrat Mangione, 26, found the note in a pair of gifted socks before a hearing on the murder of Brian Thompson, but he refused to put them on because they didn’t match his style.

Mangione knew he was going to make a splash at his latest New York City court appearance, so he groomed himself carefully for the cameras, prosecutors claimed in court docs released Wednesday.

Before the February 21 hearing, he rifled through some gifts from out-of-touch supporters and stumbled upon two heart-shaped notes hidden in a pair of gifted socks.

The handwritten note encouraged Mangione to “keep your head held high” and “know there are thousands of people wishing you luck.” The author then referenced a Reddit community, signing the note with “K / Free Luigi.”

The other letter was addressed to someone named Joan and thanked them for “trusting me.”

Despite being caught with the contraband, Mangione was allowed to wear the fresh pair for his court appearance.

However, in a bizarre move, Mangione went on to take the socks off right before his hearing because they didn’t suit his outfit, prosecutors said.

Since the letter came to light, obsessive fans have gone to war with each other, brawling about whether the note should have been written.

Some unhinged Reddit users on the Free Luigi page fear the gushing love for the accused killer could hurt his longshot case ahead of the trial.

One person wrote, “I, as a lawyer, would be livid if some uninformed, delusional fangirl […] f****d with my client’s case like this.

“Whoever did this – you’re not cute, you’re not smart, you’re not helping, and no serious professional person involved with this case would feel anything but disgust and anger towards you for this idiocy.”

Others agreed and blasted the fan, all the while insisting that supporting Mangione is a “just cause.”

“Prisons are notorious for doling out punishment for minor things that we may think of as nothing is everyday situations,” wrote another concerned fan.

Meanwhile, some more die-hard supporters defended the letter writer and believed they “meant well.”

“The real issue is why his representatives gave him these socks instead of simply buying socks for him themselves,” wrote the user.

LUIGI’S DEMANDS

Mangione is facing three separate indictments in New York, Pennsylvania, and by the Department of Justice over the murder of UnitedHealthcare CEO Thompson, 50.

Thompson, who was a dad of two, was brazenly shot in the back of the head by a masked assassin on December 4 as he walked across the street into a conference in New York City.

The killer evaded capture for days, despite being caught on surveillance flashing a smile and staying at a hostel in Manhattan.

On December 9, Mangione was arrested, and he became an overnight sensation as far-left supporters gushed over his appearance and motive of lashing out at “parasitic” insurance companies.

Since he was taken into custody, the alleged assassin has made some brazen demands, the docs unsealed Wednesday reveal.

He allegedly wanted a laptop to review legal documents, but was laughed off by prosecutors who claimed he was getting “special treatment.”

“Special treatment to the defendant’s benefit was violated when [prosecutors] made accommodations for defendant’s fashion needs during the last court appearance,” prosecutor Joel Seidemann wrote in a document.

Mangione’s impact was made crystal clear on the day of his last hearing, as a mass of supporters gathered in New York City with signs professing their love for him.

Fans dressed up like the fictional video game character Luigi and cried for the accused killer to be released.

“We the people want Luigi free. Who’s the real terrorist? UHC,” chanted the crowd.

FROM PENN TO PRISON

Mangione was born to an elite family in Maryland as his grandparents had amassed a fortune developing real estate.

His family shelled out tens of thousands of dollars to send him to the private all-boys secondary school Gilman before he went to the University of Pennsylvania in 2016.

Mangione was the valedictorian of his high school and earned a bachelor’s and master’s in computer engineering at the Ivy League university.