A 20-year-old from a Pittsburgh suburb has been identified as the shooter in the apparent assassination attempt on former President Donald Trump.

Authorities have named the suspect as Thomas Matthew Crooks from Bethel Park, Pennsylvania. Crooks opened fire at the rally on Saturday, just days before Trump was to accept the Republican nomination for a third time. Secret Service agents fatally shot Crooks at the scene.

An FBI official stated late Saturday that the motive behind the attack is still unknown. In addition to the fatality, two spectators were critically injured in the incident.

Law enforcement sources revealed to the Associated Press that bomb-making materials were discovered in Crooks' vehicle and at his residence. These officials, who spoke on condition of anonymity, were not authorized to publicly discuss details of the ongoing investigation.

Investigators have determined that the weapon used in the shooting was purchased by Crooks' father at least six months prior. Federal agents are currently investigating how and when Crooks acquired the gun and are gathering further information about him.

A blockade was established on Sunday to restrict traffic near Crooks' house, located in a blue-collar Pittsburgh neighborhood of modest brick homes.

Crooks' political affiliations remain unclear. While records indicate he was registered as a Republican voter in Pennsylvania, federal campaign finance reports show he donated $15 to a progressive political action committee on January 20, 2021, the day President Joe Biden was inaugurated.

Public court records in Pennsylvania show no previous criminal cases involving Crooks.

The FBI disclosed Crooks' identity early Sunday morning, hours after the shooting. Authorities reported that Crooks was not carrying identification, necessitating the use of DNA and other methods to confirm his identity.

A person familiar with the matter, speaking on condition of anonymity, confirmed that an AR-style rifle was recovered at the scene.

An analysis by the Associated Press of over a dozen videos and photos from the Trump rally, as well as satellite imagery, revealed that the shooter managed to get close to the stage where Trump was speaking.

A geolocated video posted on social media shows the body of a person wearing gray camouflage lying motionless on the roof of a building at AGR International Inc., a manufacturing plant just north of the Butler Farm Show grounds, where Trump's rally was held.

The roof where the body was found was less than 150 meters from Trump's speaking location, a distance from which a skilled marksman could reasonably hit a human-sized target. For context, U.S. Army recruits must hit a scaled human-sized silhouette at this distance to qualify with the M-16 rifle.

Federal agents are still working to determine when and how Thomas Crooks obtained the weapon, according to law enforcement officials who spoke to the Associated Press on condition of anonymity.