Larry Rendell Brock -- the retired Air Force lieutenant colonel who's one of the Capitol insurrectionists last week -- can thank his ex-wife for his arrest.
As we reported -- Brock was the guy photographed holding zip ties inside the Senate chamber and was pretty easy to ID as he was decked out in body armor, a military helmet and a tag with a Punisher skull ... but his former spouse provided further intel to law enforcement.
According to a federal affidavit ... Brock's ex-wife of 18 years called the FBI National Threat Operations Center (NTOC) on Friday to turn him in.
The woman told the feds she recognized him from his military getup, adding ... "I just know that when I saw this was happening I was afraid he would be there. I think you already know he was there. It is such a good picture of him and I recognize his patch."
The affidavit says a second witness also reported Brock to the FBI the same day, telling the authorities ... "It looks like him and he has pilot wings on his chest in this picture. He was an A-10 pilot. Worked at L3, and he still has contacts that work with L3 that knew he was flying to Washington DC."
Brock was arrested shortly afterward and is facing one count of knowingly entering or remaining in any restricted building or grounds without lawful authority, and one count of violent entry and disorderly conduct on Capitol grounds.
As for why he did what he did, he says it's because "The President asked for his supporters to be there to attend, and I felt like it was important."
He has denied any nefarious intentions with the zip ties though, claiming he found them inside the Capitol and planned to return them to police.