(CNN) — The man who sold a semi-automatic weapon that was later used to take hostages in a Texas synagogue in January has pleaded guilty to a federal firearms charge, according to a release from the U.S. Attorney’s Office for the Northern District of Texas.

Henry “Michael” Dwight Williams, 32, admitted Thursday to being a felon in possession of a firearm.

“This defendant, a convicted felon, had no business carrying — much less buying and selling — firearms,” U.S. Attorney Chad Meacham said in a news release. “Whether he suspected his buyer would use the gun to menace a community of faith is legally irrelevant: In the U.S., convicted felons cannot possess firearms.”

The original complaint, filed in January 2022, stated Williams sold a semiautomatic Taurus G2C pistol to Malik Faisal Akram, who later used it to hold four people hostage at Congregation Beth Israel synagogue in Colleyville, just outside Dallas-Fort Worth.

Akram, a 44-year-old British national, was shot to death by federal agents after an hours-long standoff on January 15. The FBI team killed Akram after one hostage was released and three escaped from the synagogue, officials said.

Seller tied to Akram via phone records

According to the release, Williams was tied to Akram via cell phone records.

“Tireless days of nonstop investigation revealed the connection of Mr. Akram to Mr. Williams, we are grateful to the many law enforcement agencies and personnel that traced the weapon’s nefarious source,” said Dallas FBI Special Agent in Charge Matthew DeSarno.

The FBI treated the standoff as “both a hate crime and an act of terrorism,” DeSarno said earlier this year, adding that Akram committed a federal hate crime “when he forcibly kidnapped four hostages while they exercised their right to worship.”

Williams was initially arrested on an outstanding state warrant and admitted selling Akram the weapon at an intersection in South Dallas after being shown a photo of the suspect, according to the news release.

As part of his plea agreement, Williams admitted to possession of the firearm despite his previous felony convictions of aggravated assault with a deadly weapon and attempted possession of a controlled substance.

Investigators believe Akram was motivated in part by a desire to see the release of convicted extremist Aafia Siddiqui, who is serving an 86-year federal prison sentence in Fort Worth, they’ve said. She was not involved in the Colleyville standoff, her attorney said.

DeSarno previously said he believes Congregation Beth Israel was targeted because it is the closest synagogue to where the suspect believed the convicted extremist was being housed.

Akram arrived in the United States in late December via New York’s John F. Kennedy International Airport, a U.S. law enforcement source familiar with the investigation told CNN.

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