HOUSTON (CBSDFW.COM/AP) — An attorney for an 18-year-old accused of fatally shooting 10 people at a Texas high school says federal prosecutors plan to file charges against the former student after they had previously indicated they would not.

Attorney Nick Poehl says Dimitrios Pagourtzis was taken into federal custody Monday and was set to appear in federal court in Galveston.

Mugshot of Texas school shooting suspect Dimitrios Pagourtzis. (credit: Galveston County Jail)

Poehl says he doesn’t know what federal charges were filed.

Pagourtzis has been charged with capital murder in state court for the May 18, 2018 shooting at Santa Fe High School in Galveston County.

Pagourtzis, who was 17-years-old at the time of the shooting, is accused of using a shotgun and pistol that belonged to his father in an attack that left eight students and two teachers dead.

Last month, the U.S. Attorney’s Office for the Southern District of Texas said no federal charges would likely be filed.

A spokeswoman for the U.S. Attorney’s Office didn’t immediately return an email seeking comment.

(© Copyright 2019 CBS Broadcasting Inc. All Rights Reserved. The Associated Press contributed to this report.)