A man is under arrest in Washington after an improvised explosive device, a rifle and some ammunition were allegedly found in his jeep, Capitol Police said Friday.

The man stopped to ask police for directions near the Capitol building at about 11 a.m. EDT Friday, at the intersection of 2nd and Independence Avenue Southeast, according to Capitol Police spokeswoman Sgt. Kimberly Schneider.

The officer responding noticed a rifle case on the car seat and inspected the jeep, discovering the IED, rifle and ammunition. A canine unit was enlisted to help.

"They've all been rendered safe right now because they're in the custody of Capitol Police," Schneider told reporters at a briefing Friday.

The officer took the unidentified man into custody; the vehicle is still being searched.

Library of Congress employees near where the jeep was stopped were evacuated, and several roads are closed while police continue their investigation.

Schneider said that it wasn't clear what the man intended to do with the cache of weapons.

The IED is on its way to the FBI facility in Quantico, Va., for analysis.