COLLEGE PARK, Md. (AP) — The FBI says a Virginia man charged with storming the U.S. Capitol told an undercover agent that he belonged to a militia-style group and coordinated surveillance efforts on the same building more than a month after the riot.

A court filing unsealed on Tuesday doesn’t specify a possible motive for Fi Duong and an associate to surveil the Capitol for weeks after the Jan. 6 insurrection. But it says an undercover agent attended meetings of Duong’s group and that investigators intercepted communications about post-riot surveillance work.

Duong isn’t charged with plotting any violence.

Prosecutors didn’t seek his pretrial detention after he was arrested on Friday. His attorney declined comment.