Criminal probe is launched in Conn. plant blast

Emergency personnel work at the site of the Kleen Energy plant, seen in this aerial photo, after an explosion in Middletown, Conn., Sunday, Feb. 7, 2010. (AP Photo/Jessica Hill)

February 8, 2010 6:41:02 PM PST
Authorities launched a criminal investigation Monday into the cause of an explosion that killed five people at a power plant under construction, saying they couldn't rule out negligence.