CHICAGO (CBS) — Confusion and the sight of lots of police cars caused a bit of commotion in downtown Chicago on Thursday afternoon after reports of an active shooter turned out to be a “drill that went terribly wrong.”

Police responded to reports of an active shooter Thursday afternoon at 225 W. Randolph St., but within minutes determined that was not the case.

“At this point it appears to have been an active shooter drill that went terribly wrong,” said Michael Pigott, 1st District Commander with the CPD. “A proper notification was not made to all people in the building. Apparently a text message went out. They were testing their system and people took that literally as they should.”

Police said that text started the chain of events bringing police there was a 10 minute time frame where authorities thought a real active shooter incident was taking place. The initial call to police did not come from the Chicago building, but then people inside the building started to call 911.

“There’s a safe way to do these types of drills. We’ll work with the building management to make sure they’re working on best practices,” Pigott said.

There are no reports of injuries.

In a statement, an AT&T spokesman said:

“A training class this afternoon caused a false alarm in the building. This was an instructional training video – not a drill or formal exercise. We’re grateful to the Chicago Police, Fire and Emergency Management teams for their swift response and we are investigating the incident.”

#BREAKING: NO ACTIVE SHOOTER. Mass panic and police response downtown at the 225 W Randolph building after someone on 7th flower reports “active shooter.” @Chicago_Police confirms that report is UNFOUNDED. Hearing on scanner this may have been a drill gone wrong. @cbschicago pic.twitter.com/67gmh2dLcO — LAUREN VICTORY (@LaurenVictory) July 18, 2019