About half of the 2,800 residents in West, Texas were evacuated Wednesday night before the blast, including a nursing home.
Many of these residents remain displaced tonight as the blast zone is still considered very volatile and dangerous.
Outfront tonight: Texas Lt. Governor, David Dewhurst with the latest.
Rescue workers continue searching for survivors among the rubble after an explosion devastated West, Texas. The small town which is about 20 miles north of Waco was almost leveled by a massive explosion at a fertilizer plant.
The blast, which was captured on cell phone video could be felt as far as 50 miles away and flattened or damaged dozens of homes. Some reports say more than 5 people are believed to be dead and more than 160 injured.
The investigation is being treated as a crime scene, although there is no proof it is anything more than an accident.
Our Miguel Marquez is in West, Texas with the story.
The FBI released Thursday images of two men. In the video you see one walking behind the other not far from the marathon finish line.
Authorities say suspect two – the man in the white hat - left a bag containing explosives at the site of the second blast.
— OutFrontCNN (@OutFrontCNN) April 18, 2013
CLICK HERE for the FBI "Seeking Information" posters.
OutFront tonight: Congressman Mike McCaul - Chairman of the House Homeland Security committee.
Resident Barry Murry talks to CNN about what he saw and heard in the explosion at the fertilizer plant.