Trump would-be assassin Thomas Crooks researched mass shooter Ethan Crumbley: source

Would-be Trump assassin Thomas Crooks researched mass high school shooter Ethan Crumbley before attempting to kill the former president, according to a source familiar with the matter.

Ethan Crumbley, now 18, is serving life in prison without the possibility of parole for killing four students and injuring seven others at Oxford High School in Michigan in November 2021, when he was just 15 years old.

Crooks looked up Crumbley before carrying out the assassination attempt at Trump's rally in Butler, Pennsylvania, on July 13, the source told Fox News Digital.

Following Crumbley's historic conviction, his parents, James and Jennifer Crumbley, were also found guilty of involuntary manslaughter. 

TRUMP SHOOTER THOMAS CROOKS' ONLINE SEARCH HISTORY INCLUDED ‘DEPRESSIVE DISORDER,’ TRUMP, BIDEN, DNC

Undated file photo of Thomas Matthew Crooks in a yearbook photo. Crooks is alleged to be the shooter in the assassination attempt on former President Donald Trump in Butler, Pennsylvania on Saturday, July 13, 2024.  (Obtained by Fox News Digital)

Prosecutors argued that the couple did not properly secure their guns and home and did not get their son the help he needed before the shooting. The parents even visited Oxford High School administrators to discuss their son's disturbing drawings he made in glass the same morning of the deadly shooting.

Crooks' other internet search history included photos of Trump and Biden, the Democratic National Convention (DNC) and "major depressive disorder," as The New York Times previously reported.

FBI'S 200 INTERVIEWS AND SEARCH OF 14,000 IMAGES LED TO … NOTHING?

Ethan Robert Crumbley, 15, charged with first-degree murder in a high school shooting, poses in a jail booking photograph taken at the Oakland County Jail in Pontiac, Michigan. (Oakland County Sheriff)

Investigators learned of Crooks' search history after cracking his phone, according to the Times.

FBI Director Christopher Wray revealed investigators' findings during Wednesday's congressional hearing, where he said the FBI has conducted 200 interviews and combed through 14,000 images on Crooks' phone.

FOLLOW LIVE UP-TO-MINUTE DETAILS OF ATTEMPTED ASSASSINATION

A drone view shows the home of 20-year-old Thomas Matthew Crooks, named by the FBI as the "subject involved" in the attempted assassination of former President Donald Trump, in Bethel Park, Pennsylvania, on July 15, 2024.  (REUTERS/Carlos Osorio)

Federal officials are still working to determine a motive behind Crooks' assassination attempt against the former president, which left former Buffalo Township Volunteer Fire Department chief Corey Comperatore, 50, dead and two others — David "Jake" Dutch, 57, and James Copenhaver ,74 — critically wounded. They are now in stable but serious condition.

Crooks also visited the rally site at least one time before Saturday's shooting, Wray reportedly said. 

Fox News' Chris Eberhart contributed to this report.

Audrey Conklin is a digital reporter for Fox News Digital and FOX Business. Email tips to This email address is being protected from spambots. You need JavaScript enabled to view it. or on Twitter at @audpants.