WASHINGTON — An accused big-time drug dealer awaiting trial in a D.C. jail is now suspected of running a heroin ring inside the jail.

Richard Byrd is charged with running a drug operation that distributed large amounts of cocaine and marijuana across the country.

He’s scheduled to go on trial Sept. 12.

In a motion filed last week, his defense attorney says prosecutors now accuse Byrd of running a heroin ring in D.C.’s Correctional Treatment Facility or CTF, as well as reaching out to a potential government witness.

Byrd’s attorney David Solomon is requesting a hearing to force prosecutors to lay out their evidence for the new accusations.

Meanwhile, the motion says on or around March 30, Byrd was placed “in lockdown” at the jail.

He had previously been part of the general population.

Editor’s note: The name of the Correctional Treatment Facility has been updated to reflect its correct name.