Police said they found improvised explosive devices and an assault weapon at a dorm in the University of Central Florida campus in Orlando.

BBC: Explosives found at Orlando university campus

Don Shepperd, a CNN military analyst, said the new weapon is not a fuel-air explosive but works on a similar principle.

CNN: Pentagon to use new bomb on Afghan caves

Security planners have drawn up procedures to deal with improvised explosive devices, suicide bombers and the use of a weapon of mass destruction.

CNN: Authorities mount record security effort to ensure inaugural safety

Still more dangerously, by treating nuclear weapons as just another explosive in the arsenal, rather than as a deterrent weapon of last resort, America would dangerously blur the line against nuclear use by anyone.

ECONOMIST: Why some weapons are best left unexplored

The investigation will focus on whether the Marines followed procedures to properly fire the weapon, whether there was a malfunction in the firing device or in the explosive mortar itself, the official said.

NPR: Mortar Explosion In Nev. Kills 7 NC Unit Marines