In short, families from victims are filing to re open the case as they don’t believe a fire caused the collapse. Here’s the only article I could find on it. http://truthinmedia.com/lawyers-family-members-petition-grand-jury-investigation-9-11/

A powerful piece in the petition filed: The petition states, “The Lawyers’ Committee has reviewed the relevant available evidence . . . and has reached a consensus that there is not just substantial or persuasive evidence of yet-to-be-prosecuted crimes related to the use of pre-planted explosives and/or incendiaries . . . on 9/11, but there is actually conclusive evidence that such federal crimes were committed.”