The 24-year-old man suspected of being behind a series of bombings in the Texan city of Austin was a home-schooled computer expert who neighbours described as quiet and unremarkable.
Mark Conditt died when a SWAT team closed in on his vehicle near Round Rock, 32km from Austin.
Police said that they had learnt of his identity in the previous 24 hours, when he had dropped off a package at a FedEx in Austin and was caught on CCTV.
They then obtained his Google search records, and found suspicious activity.
Conditt lived in the Pflugerville suburb of Austin - close to the home of his parents.
"I am not that politically inclined. I view myself as a conservative, but I don't think I have enough information to defend my stance as well as it should be defended.
"The reasons I am taking this class is because I want to understand the US government, and I hope that it will help me clarify my stance, and then defend it."
His postings show him to be of moderate conservative leanings - against gay marriage and abortion, and in favour of the death penalty.
Conditt posted a photo her son in February 2013 on Facebook, saying: "I officially graduated Mark from High School on Friday. 1 down, 3 to go. He has 30 hrs of college credit too, but he's thinking of taking some time to figure out what he wants to do....maybe a mission trip. Thanks to everyone for your support over the years."
After completing his studies Conditt worked at Crux Semiconductor Manufacturing in Austin, and had been previously employed as a computer repair technician.
His work at Crux will certainly come under the scrutiny of police, as they try to piece together how he obtained the bomb-making equipment. TMZ reported that at Crux his role was "purchasing agent/buyer/shipping and receiving" for the company, which is involved in robotics, mechanical repair and metal products.
Investigators have detained two roommates of the Austin bombing suspect. One roommate was detained, questioned and released. The other is currently being questioned. Their names will not be released because they are not under arrest at this time. APD PIO
— Austin Police Department (@Austin_Police) March 21, 2018
Austin bombing suspect argued against gay marriage and abortion online https://t.co/IkcQAi3rDO