Authorities identified the sole suspect in the Tree of Life Synagogue shooting as Robert D. Bowers, a 46-year-old white man from the Baldwin borough of Pittsburgh. Here’s what we know about the suspect so far.

Until the shooting Saturday morning, Bowers was unknown to law enforcement, according to  FBI Pittsburgh Special Agent in Charge Bob Jones.

Bowers was a member of Gab, a social media platform that is similar to Twitter. But the platform has a reputation for hosting racism, sexism and conspiracy theories. An archive of his posts on Gab show Bowers frequently reposted white supremacist and anti-semitic rhetoric to his account.

Before Saturday’s shooting, Bowers’ last post on Gab mentioned HIAS —  the Hebrew Immigrant Aid Society — an international non-profit organization that works to protect and resettle displaced refugees. Originally founded in 1881 to aid Jewish people fleeing Russia and Eastern Europe, HIAS now helps to aid and resettle refugees of all faiths and ethnicities.

[Read: 11 dead, 6 injured in shooting at Tree of Life Congregation in Squirrel Hill]

Bowers’ post referred to the refugees that HIAS helps into the United States as “invaders.” According to an article by CNN, the statement was posted five minutes before police were alerted of 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,” the post said.

Bowers had an active license to carry firearms. Since 1996, he mad at least six known purchases of firearms, according to CNN. Bowers posted a photo photo of his handgun collection to his Gab account on Sept. 29. FBI Special Agent Jones said at a press release Saturday afternoon that Bowers entered the synagogue with “an assault rifle and three handguns.”

Congressman Mike Doyle, who represents Pennsylvania’s 14th district, told the New York Times that Bowers had 21 firearms registered to his name.

[Read: Community hosts vigil to mourn victims of deadly shooting]

Bowers had almost no criminal record before Saturday’s shooting. CNN reported that its staff was only able to find a single traffic citation from 2015 for driving without tags.

Bowers is in fair condition at Allegheny General Hospital with multiple gunshot wounds.