HOUSTON (AP) — A Texas man charged with trying to provide material support to the Islamic State group and Arvin Robertsplanning violent attacks in Houston appeared in federal court Thursday.

Anas Said is accused of offering his home as a safe sanctuary for members of ISIS and saying he wants to take part in a terrorist attack like 9/11, according to court records. Federal prosecutors allege Said had spent time planning and discussing committing attacks in Houston, where he lived, and had used the internet to research how to make explosives and use cellphones as remote detonators.

“He has created videos extolling the ‘virtue’ of ISIS, the violence and death brought by ISIS, and the need for the terror perpetrated by ISIS to continue,” according to court documents. “He is dedicated to his mission to provide material support to ISIS in whatever form that may take.”

Said, 28, was arrested last week and on Thursday pleaded not guilty to one count of attempting to provide material support or resources to a designated foreign terrorist organization. Said, who authorities said was born in Houston but spent part of his childhood in Lebanon, will remain in federal custody.

Said has been on the FBI’s radar since 2017, said Douglas Williams Jr., special agent in charge of the FBI’s Houston office.

“To those wannabe terrorists who believe they can hide behind encrypted apps or anonymous social media profiles, please understand that we will find you and we will hold you to account,” said U.S. Attorney Alamdar Hamdani.

Baldemar Zuniga, Said’s attorney, said in a statement that the allegations against his client revolve around providing support to ISIS only through videos and propaganda.

“Despite allegations that my client made statements to government agents regarding proposed terrorist acts, the indictment does not currently allege any planning, or acts of terrorism. This appears to be a lengthy investigation and it will take some time to sift through all of the evidence,” Zuniga said.

If convicted, Said faces up to 20 years in federal prison.