TAMPA, Fla. — The U.S. Department of Justice charged a Tampa man with attempting to provide material assistance to ISIS, saying he procured weapons that he planned to use in an attack on that group's behalf.

Investigators say Muhammed Momtaz Al-Azhari, 23, attempted to buy guns illegally that he planned to use in an attack. FBI agents arrested Al-Azhari on May 24 after he took possession of the weapons.

According to the Department of Justice's criminal complaint, Al-Azhari has a criminal history that includes prior terrorism charges in Saudi Arabia. In the course of the investigation, Al-Azhari reportedly expressed admiration for the Pulse nightclub shooter and wished to carry out a similar shooting. He's formally charged with attempting to provide material support or resources to a designated foreign terrorist organization.

The task force that investigated Al-Azhari included elements of the Tampa Police Department, the Pinellas County Sheriff's Office, the Hillsborough County Sheriff's Office, the Pasco Sheriff's Office, the St. Petersburg Police Department, the Clearwater Police Department, and the Florida Department of Law Enforcement.

If convicted, Al-Azhari faces a maximum penalty of 20 years in federal prison.