Three days after the Boston Marathon bombings federal agents have released images of the men responsible for the deadly attack.
Late Thursday the FBI released pictures and video of the men they have labeled as suspects.
They know their faces and they hope the public can help provide their names.
"Identifying those responsible is our top priority," said FBI Agent In Charge Richard DesLauriers.
Meanwhile, NBC News has learned that detectives have visited several Boston area hobby stores trying to determine where electrical components to build the deadly bombs may have been purchased.
Three people were killed and more than 160 others were wounded in the Monday bombings.
-- Jay Gray, NBC News, reports