The volatile behavior of a man suspected of carrying out a mass shooting in downtown Minneapolis on Wednesday had been well-documented by officials in various county and city agencies. It did not stop him from having the ability to possess the firearm that was used to allegedly carry out a shocking act of violence.

Minnesota officials named Carlton Neal Johnson II as the suspect in a Sept. 2 shooting that left two people dead. Here's what we know about him.

Multiple people have been shot, including a police officer, at an active shooter scene on the south side of downtown Minneapolis. Police and emergency responders have converged in the Loring Park neighborhood on a report of multiple casualties,

The shooting in a Minneapolis apartment building left three people dead and several other injured, including three police officers. Investigators remained on the scene Thursday, as residents of the building waited to be allowed back home.

He had threatened his neighbors, repeatedly showed off his pistol, and warned he was planning to shoot people, according to building residents, court documents and law enforcement officials.

A gunman shot two Minneapolis police officers, killed two people and injured three others at an apartment building near Loring Park on Wednesday evening. Another officer was also injured. The suspected gunman was identified as Carlton Neal Johnson II,