A big misunderstanding led to a big mess that involved San Antonio police officers blocking off downtown streets and evacuating a building on W. Houston Street Wednesday morning.

Sgt. Devon Lambert said police received a call around 9 a.m. from a woman in a nearby high rise, saying she saw armed men dressed in dark clothing with their faces covered on top of the old Alameda Theatre building, in the 300 block of W. Houston Street.

The woman also told police the men appeared to have long guns with them, he said.

Police launched their helicopter, and from above, also noticed what appeared to be suspicious activity, Lambert said.

"The police helicopter was saying that it appeared they were trying to stay out of his vision,” he said. "We responded like there were people on the roof with guns that might have bad intentions.”

Officers blocked off streets in the area, and after evacuating a construction crew from the site, stormed into the building with their rifles drawn.

Jeremy McKinney said he and his co-workers, who are remodeling the old theatre, suddenly got an unscheduled break.

"We were just sitting there working and the foreman let us know that we needed to go outside,” McKinney said. “As we were on our way out, we noticed the police officer and they told us to cross the street."

McKinney said his first thought was there had been a gas leak or other construction related problem.

He said seeing the armed officers file past him caught him off guard.

“All the heavy machinery, or the heavy artillery, weapons and stuff like that,” he said.

About an hour after the incident began, officers gave the all-clear, allowing the crew to go back to work.

Lambert said they found out the men on the roof were actually air conditioning workers, part of the construction crew.

What had been thought to be weapons were actually black foam insulation tubes, about the size of a rifle, he said.

“I guess from a couple of hundred feet away, it could look like that,” Lambert said.

Passersby, meanwhile, got an eyeful, watching all the activity.

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