Third suspect indicted in attack on Texas 'Draw Mohammed' event
Members of the FBI Evidence Response Team investigate the crime scene outside of the Curtis Culwell Center after a shooting occurred the day before, on May 04, 2015 in Garland, Texas (AFP Photo/Ben Torres)

A federal grand jury has indicted an Arizona man on conspiracy and weapons charges for aiding in the May attack on an event in Texas to draw the Prophet Mohammed, according to court papers released by Arizona media on Tuesday.

A federal grand jury indicted Abdul Malik Abdul Kareem, also known as Decarus Thomas, on three counts of aiding in the attack in the Dallas suburb of Garland, according to the indictment posted on the website of Phoenix TV broadcaster 12 News. The attack left dead the two gunmen who carried it out.

Roommates Elton Simpson and Nadir Soofi of Phoenix were killed by a Garland police officer and four Garland Police SWAT team members when they opened fire with assault rifles outside the cartoon drawing event.

The indictment said Kareem supplied arms to the pair and helped prepare them for the attack. It also indicated there may have been other people involved in the plot.

"On dates between January 7, 2015 and May 3, 2015, Kareem hosted Simpson, Soofi, and other persons known and unknown to the grand jury inside his home to discuss the Muhammad Art Exhibit and Contest and their plan to travel from Phoenix, Arizona, to Garland, Texas, to conduct an attack on the contest," the indictment said.

Kareem is due to appear in a federal court in Arizona later on Tuesday.