A man was taken into custody early Friday in connection with an investigation into a suspicious vehicle near the Pentagon, U.S authorities confirmed.

Pentagon police spokesman Chris Layman said one or two other people may have been involved. The car was in bushes near the Pentagon's north parking lot, Layman added.

The suspect is a naturalized U.S. citizen who came to the country from Ethiopia.

He was walking around Arlington Cemetery in the middle of the night and a vehicle that he had been operating was in "close proximity" to the Pentagon.

The authorities also found that a notebook that contained threatening words like "Al Qaeda" and "Taliban," at the scene.

The vehicle turned out to be a Honda Pilot and the suspicious pack was found inside. The authorities said that as the men refused to cooperate they were forced to arrest him.

Due to the investigation U.S authorities have today closed several major roads around the Pentagon.