POPLAR BLUFF, Mo. -- The identity and motives of an alleged gun-toting man in black that caused a Poplar Bluff High School lockdown Tuesday remain unknown. Police say surveillance footage failed to produce clear images of the individual.

The campus was placed in lockdown at 8:08 a.m. Tuesday after a teacher saw a man walking near campus at the intersection of Westwood and Harper streets with what appeared to be a rifle.

"We got the guy on video on the west side of (U.S.) 67, but the video is poor," Poplar Bluff police deputy chief Jeff Rolland said. "At one point, it looks like it could be a shotgun, but then it looks like an umbrella."

The teacher was the only one to see the person, which police say is unusual. If a man was carrying a rifle near the high school, Rolland said police would receive several calls.

"Usually, when somebody is carrying a gun around, we get a plethora of calls. This only had one call, and that was it. There are definitely more people who saw him, but it didn't alarm them," Rolland said.

The lockdown was lifted an hour later after officials confirmed the possible threat had subsided.

Police confirmed there is nothing illegal about walking down the road with a rifle or shotgun. Taking the firearm onto the campus would be a different matter.

"We would have just talked to him and seen what was going on, and that would have been it," Rolland said. "With the Safe Schools Act, it would be a federal charge to bring a firearm onto school property. Unless he was a convicted felon or using it in a threatening manner, it's perfectly legal to possess a firearm," Rolland said.

Pertinent address:

Westwood Street and Harper Street, Poplar Bluff, Mo.