DALLAS (CBSDFW.COM) – A 23-year-old man from Dallas had pleaded guilty to a terrorism charge after officials said he left the U.S. to fight on behalf of ISIS, the Department of Justice announced Wednesday.

Officials allege Omer Kuzu spent five years providing communications support for ISIS. He was captured by Democratic Syrian Forces in 2019 and was returned to the U.S.

According to court documents, Kuzu admitted that he left Texas with his brother, Yusuf, for Turkey in 2014 and was then picked up by an “ISIS taxi.” He and his brother then allegedly spent five days training with ISIS before being sent to Syria.

Officials said Kuzu claimed he worked as an “ISIS telecommunications directorate” and then pledged allegiance to ISIS leader Abu Bakr al-Baghdadi.

Kuzu, along with 1,500 other suspected ISIS fighters, was captured in March 2019. He was handed over to the FBI and was charged with conspiring to provide material support material to ISIS.

According to court documents, the 23-year-old admitted to engaging in terroristic activities. After pleading guilty, he faces up to 20 years in federal prison. Sentencing is set for January 2021.

“This defendant, an American citizen radicalized on American soil, pledged allegiance to a brutal terrorist group and traveled halfway across the world to enact its agenda,” said U.S. Attorney Erin Nealy Cox. “The United States must do everything we can to prevent and deter this type of radicalization and prioritize prosecution of those that support the terroristic agenda of ISIS. I am gratified Mr. Kuzu faced justice in an American court.”

“Preventing terrorism remains the FBI’s top mission priority. The defendant intentionally left the United States to join, train with, and fight on behalf of ISIS. The North Texas Joint Terrorism Task Force worked closely with our domestic and foreign partners to ensure the threat he posed was mitigated,” said FBI Dallas Special Agent in Charge Matthew DeSarno. “We remain vigilant in our effort to prevent terrorism as well as hold terrorists, and those who provide support to terrorist organizations, accountable for their actions.”