FT. LAUDERDALE (CBSMiami) – The Ft. Lauderdale police bomb squad entered a religious school near Federal Highway Friday morning, after a science teacher found a vial containing a potentially explosive chemical.

According to police, the building was evacuated as a precaution, but no immediate danger was found.

READ MORE: Bennett, Barkov Lift Panthers Over Golden Knights 4-1

The vial was believed to contain Ammonium Nitrate, a chemical used in fertilizer and also in bombs, such as the explosive device used in the recent Norway bombings, and the attack on the Federal Building in Oklahoma City.

Matt Little, a spokesperson for the Ft. Lauderdale Police Department, said no students were in the Bethany Christian School on SE 9th Street when the science teacher, a new employee whose name is not yet available, discovered the vial.

Police said the vial was part of a science kit, the teacher noticed the chemical had become crystalized, which makes it potentially explosive.

“It was a kit, a chemical kit in a science lab and it somehow accidently did get contaminated, but it perfectly was appropriate to have a kit in the science lab,” Little said. “It just got contaminated and that’s what made it potentially explosive.”

READ MORE: Miami Weather: Temps In The 30s This Weekend

Approximately 30 teachers were evacuated and the bomb squad was called in.

From chopper 4, two members of the squad dressed in protective gear were seen entering the building about 9:30 Friday morning. About 15 minutes later, they left carrying a small box, which they placed in a protective containment device on the street outside of the school.

Little said two other vials were also removed from the school, and all will be taken for analysis to figure out if they are, in fact, explosive.

The fire department said there was not criminal intent in this case.

The activity at the school caused parts of Federal highway, US1, to be shut down for about an hour, but the street has reopened.

MORE NEWS: Mistaken Identity Lands Coconut Creek Man In Jail For Five Days

Teachers have been allowed to return to the school.