Enrique Marquez, the friend who provided rifles used in the San Bernardino shooting, was charged Thursday for his role in plotting earlier attacks with one of the shooters, federal officials said.

Marquez was cooperating with law enforcement officials in their investigation, and a newly released criminal complaint appears to show that he has turned into an open book.

Below are some of the most surprising and interesting details from the complaint. (You can read the entire thing here.)

1. The 911 call: “The f—— a—— used my gun in the shooting”

Marquez called 911 soon after the Dec. 2 shooting to share his connection to the attack.

2. Marquez: “I’m involved”

One day after the shootings, Marquez went to the emergency room at the UCLA Harbor Medical Center. There, he admitted to knowing Syed Rizwan Farook for nearly a decade and told the medical staff, “I’m involved.”

3. Marquez provided materials used in the IED left in the attack

Marquez told law enforcement that he and Farook read instructions on how to create an improvised explosive device and that he himself bought materials used to create the improvised explosive device (IED) left at the site of the shooting.

Note: Black bars represent ellipses.

4. Marquez planned earlier attacks

Marquez told officials that he and Farook began conspiring in late 2011 to carry out at least two other attacks in Southern California, both of them designed to “maximize the number of casualties that could be inflicted.”

Those plans included a rush hour attack on State Route 91, which runs through Riverside:

And another attack on Riverside City College:

5. Marquez bought firearms to avoid profiling

The pair decided that Marquez should purchase firearms needed for the proposed attack, in order to avoid Farook being profiled.

On Nov. 14, 2011, Marquez purchased a $660 Smith & Wesson rifle. He subsequently bought another firearm — an Oracle rifle — on Feb. 22, 2012, for $670. (Both prices exclude taxes or fees.)

The firearms were later used on Dec. 2 in the attack at the Inland Regional Center and the gunfight with law enforcement that killed both attackers the same day, the complaint states.

6. Marquez’s path to Islam

The criminal complaint also outlines Marquez’s introduction to Islam, along with the radical views to which he was exposed.

Note: Black bars represent ellipses.

7. Marquez backs away from Farook

During the first half of 2012, Farook began making trips to gun ranges as Marquez allowed their relationship to slowly dissolve.

This post, originally published on Dec. 17, has been updated.

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