A 24-year-old Texas man is facing multiple charges for allegedly advertising, selling and attempting to sell illegal firearms and gun parts while incarcerated.

During an interagency press conference in Manhattan on Tuesday, Manhattan District Attorney Alvin Bragg said the case demonstrates the confluence between illegal guns and extremism that law enforcement officials are seeing more of.

During the event, officials displayed some of the guns and gun parts prosecutors said Hayden Espinosa, of Corpus Christi, sold and tried to sell from prison.

"The first were two autoseers," Bragg said. "One for an AR-15-style rifle and another for a Glock-style handgun. For those who may not know, autoseers are a rapid-fire modification device which can transform a semi-automatic firearm into a machine gun. Incredibly powerful devices."

Espinosa is accused of committing the crimes from his Louisiana prison cell while serving a 33-month federal prison sentence in a as part of a separate case involving illegal firearms. Law enforcement officials said he did so by moderating a channel on the messaging app telegram that was geared toward racially and ethnically motivated extremism.

"We see this sad and tragic combination far too often at the intersection of gun trafficking and gun violence and hate and extremism," Bragg said.

Bragg said the multiagency investigation began 2022 after discovering the convicted shooter in the Buffalo mass shooting had visited the app channel.

"The initial discovery of this telegram chat was one that Payton Gendron had frequented so that's the genesis of the case," said NYPD Deputy Commissioner for Intelligence and Counterterrorism Rebecca Weiner.

“Mr. Espinosa and other members of the forum were assessed to hold racially and ethnically motivated violent extremist ideologies, including white supremacist and neo nazi iconography," said Darren McCormack, deputy special agent in charge of Homeland Security Investigations New York Field Office.

Espinosa is accused of using cell phones to sell or attempt to sell weapons and parts to an undercover NYPD officer from August to November 2023 and attempting to use the U.S. Postal Service to ship them.

It's unclear how Espinosa was using the postal service to ship illegal guns and parts to customers. Charges include four counts of transportation of a firearm, machine gun, silencer, or disguised gun and one count of attempted criminal sale of a firearm.

The NYPD said their involvement in the case is part of its crackdown on illegal gun sales.

"The NYPD took roughly 6500 illegal guns off our streets in 2023," Weiner said. "We’re in track to do the same. We've recovered nearly 3,000 in 2024."

Espinosa is in the custody of local Louisiana authorities and will be extradited to New York at the end of this month. He is scheduled to be arraigned in New York State Supreme Court on June 24.