Earlier on Wednesday, investigators were tight-lipped about developments in the case and did not identify any suspects.
Initial press reports after the Monday afternoon explosions focused on an injured 20-year-old Saudi man. He was cleared by investigators, who searched his apartment Monday night.
CBS News reported Wednesday afternoon on Twitter, "JUST IN: Man sought as possible suspect is WHITE MALE, wearing white baseball cap on backwards, gray hoodie and black jacket."
Three people died in the bomb blasts and more than 170 were wounded.