ORLANDO, Fla. -

An explosion occurred at a vacant downtown Orlando warehouse on Thursday, shaking buildings blocks away and forcing officials to close area roadways.

The blast occurred around 12:30 p.m. at 47 West Jefferson Street, a former warehouse for Showbiz Pizza, near Robinson Street and State.  It's not yet known if the building was occupied at the time of the explosion, but no injuries were reported.

IMAGES: Explosion in downtown Orlando

Orlando fire officials said the explosion was likely caused, at least in part, by a ruptured acetylene tank, similar to the kind used for welding.  It's unclear, however, what caused the tank to explode, fire officials said.

Aerial video showed a wall of the building blown out, exposing both floors inside with debris scattered into a lot near some railroad tracks.

The blast was felt blocks way, according to employees in other downtown buildings.

Several people who work downtown took to Twitter to describe the incident.

"OMG big explosion DT just shook my building lord be with these folks Downtown. #Orlando Idk what just happened," Kennieth Jones tweeted.

“Never a dull moment in Downtown Orlando. Yesterday was five accidents, today an explosion. Probably the scariest thing I've ever felt/seen,” tweeted mrswatsonweisel.

There are several road closures in the area.