DENVER (KDVR) — One of the weapons used by the suspect in the Club Q shooting was a “ghost gun,” sources tell FOX31.

Ghost guns are made by individuals using parts that can be purchased and assembled, or 3D printed. A privately-made gun without a serial number is difficult or impossible for authorities to trace.

Suspect Anderson Lee Aldrich is accused of killing five people and wounding at least 17 more on Saturday at Club Q, a well-known club for the LGBTQ community in Colorado Springs. An attorney for Aldrich said in a court filing Tuesday that Aldrich is nonbinary and uses they/them pronouns.

It’s unclear where Aldrich may have gotten the gun — whether they bought the parts online and assembled it or bought it from someone else.

Sources tell FOX31 that the long gun used in the shooting was a ghost gun. It appeared to be fully automatic, sources say, allowing the firing of at least 40 to 50 shots before good Samaritans tackled the suspect.

Aldrich, 22, was released from the hospital on Tuesday to the El Paso County jail and is expected in court on Wednesday morning.