AUSTIN, Texas — The family of a Muslim boy who was arrested last year after taking a homemade digital clock to a Dallas-area high school sued the Texas school district and the city where he once lived Monday, saying they violated the teenager’s civil rights.

The suit, filed in federal court on behalf of Ahmed Mohamed by his father, claims the Irving Independent School District and the city west of Dallas had discriminated against the teen because of his religion, which it said was a factor in his arrest.

The school district in a statement denied violating the student’s rights and said it could provide no further comment because the matter was in litigation.

The family has previously demanded $15 million from the city of Irving and the school district.

The 2015 arrest of Ahmed Mohamed, then a 14-year-old bespectacled ninth-grader who dabbled in robotics and attended high school in Irving, had ignited a social media firestorm.

Irving police accused him of making a hoax bomb.

“The only way to get justice is through money,” Mohamed told a news conference in Texas on Monday.

After Mohamed was seen in a NASA T-shirt in handcuffs, the Twitter hashtag #IStandWithAhmed trended globally, and the teenager was praised by Facebook Chief Executive Officer Mark Zuckerberg, who said, “Having the skill and ambition to build something cool should lead to applause, not arrest.”

A few months after the incident, Ahmed and his family moved to Qatar after the teen accepted an offer from the Qatar Foundation to study at its Young Innovators Program. The announcement of the move came a few hours after Ahmed visited the White House for an astronomy night hosted by President Barack Obama.

The teen, a U.S. citizen, returned to the United States a few weeks ago for summer vacation and plans to return soon to Qatar to attend a private school after receiving death threats in the United States.

“I lost my home, I lost my creativity. I used to love building things but now I can’t,” he said at the news conference. “I’ve lost my security.”