The suspect in Saturday's deadly shooting at a Pittsburgh synagogue, identified by officials as local resident Robert Bowers, is to face federal charges that carry the death penalty.
Here is what is known so far about the suspect, who reportedly yelled "all these Jews must die!" as he launched his attack, killing 11 people and wounding six more.
The suspect was in fair condition with multiple gunshot wounds at Allegheny General Hospital, according to Pittsburgh's public safety director.
Bowers, 46, appeared not to have a previous criminal record, and an FBI official said he was not previously known to law enforcement.
Bob Jones, special agent in charge of the FBI's Pittsburgh office, said law enforcement authorities thought the suspect acted alone, but they had not identified his full motive.
Bowers has a license to carry a firearm and has made at least six firearm purchases since 1996, CNN reported, quoting a law enforcement official.
Authorities said Bowers was armed with an assault rifle and at least three handguns when he burst into the Tree of Life Synagogue.
The U.S. Department of Justice said it would file hate crime and other criminal charges against Bowers, who could face the death penalty if convicted.
Social media posts
Bowers appeared to be the author of a recent rash of violently anti-Semitic posts on social media, notably on the Gab.com social networking website, where conspiracy theories — like a discredited report linking Hillary Clinton to pedophiles — are common.
A quote atop the Bowers page said "Jews are the children of Satan," according to screenshots of the now-suspended account released by the SITE Intelligence Group, which monitors extremist movements.
Bowers posted on Gab just hours before the shooting: "HIAS likes to bring invaders in that kill our people. I can't sit by and watch my people get slaughtered. Screw your optics, I'm going in."
HIAS is the acronym for the Hebrew Immigrant Aid Society, which has offices in New York and Maryland.
Another missive posted 17 days before Saturday's attack accused HIAS of bringing "in hostile invaders to dwell among us" — and appeared to threaten one of the organization's projects.
"We appreciate the list of friends you have provided," the poster wrote, while linking to an event page for a "National Refugee Shabbat."
HIAS called the attack a "horrifying tragedy," saying "this loss is our loss."
In another post reported by The New York Times, Bowers said he did not care for President Donald Trump because Trump was “a globalist, not a nationalist."
Using a slur for Jews, he said, "There is no #MAGA, as long as there is a k--- infestation." MAGA refers to Trump's Make America Great Again slogan.
Gab, a popular site with white nationalists and members of the so-called alt-right, released a statement saying it had "zero tolerance" for violence or terrorism and was "saddened and disgusted by the news" from Pittsburgh.
Gab said in a post that after learning of the attack, it matched the name of the alleged shooter to the holder of his account.
It then took down the Bowers account and immediately contacted the FBI, adding, "We will do everything in our power to work with law enforcement to see that justice is served."