Update:

The US Marshal's Office confirms the suspect driving the tractor-trailer is in custody Wednesday afternoon; no use of force reported.

According to officials, the Western District received a collateral lead from the Eastern District of Virginia in an attempt to locate the fugitive.

Wednesday morning, authorities were alerted of a suspicious vehicle and later initiated a traffic stop on the vehicle.

The name of the suspect has not been released at this time.

Original story:

Police activity is causing back-ups on I-581 near the Elm Ave. exit Wednesday morning.

Viewer pictures and video show law enforcement surrounding a tractor-trailer.

Both Roanoke City Police, and State Police tell us this is a US Marshal operation.

State troopers are assisting.

VDOT reports the incident occurred at 10:56 a.m.