The NY Post, CBS and Fox are among the outlets reporting that authorities have questioned a Saudi national as a “person of interest” in the Boston bombings. Fox reports that the individual is from a prominent Saudi tribe centered near the Saudi Arabia-Yemen border.

The man is reported to be 20 years old. He was questioned by the FBI and local police and his apartment was searched. He has not been arrested or charged. The Post reports on what he is believed to have said when police picked him up.

The sources said that, after the man was grabbed by police, he smelled of gunpowder and declared, “I thought there would be a second bomb.”

He also asked: “Did anyone die?”

The two bombs were reportedly packed with ball bearings to act as shrapnel and maximize casualties.

Investigators are calling on anyone who took video or photos at the scene to bring them in for examination. Any clue may help. Online speculation has focused on a man who appears on the roof of a building near the finish line. Chances are, he was just a spectator, but at this point anything may turn out to be a clue.