The station quotes St. Louis County police spokesman Brian Schellman as saying officers responded to a report of four men wearing ski masks armed with shotguns, as well of reports of shots fired in the area.
When they arrived, he says, they found more than two dozen suspects fleeing on foot.
At one point, an officer confronted a suspect who, Schellman says, pulled a handgun on the officer.
"In fear for his life, the officer shot the subject," Schellman continued. He was taken to a hospital in critical condition. The suspect's handgun was recovered at the scene.
Separately, said Schellman, one person was injured in a drive-by shooting in Ferguson early Wednesday.
He said the incident involved several males in a black sedan, and a female was shot once in the head. He said she was taken to a hospital with injuries that did not appear life-threatening.
Schellman said the shooting occurred in the same vicinity as the protests over the death of 18-year-old Michael Brown.
Meanwhile, the Rev. Al Sharpton pressed police Tuesday to release the name of the officer who shot Brown, an unarmed black teenager, and he pleaded for calm after two nights of violent disturbances over Brown's death.
There were more protests in Ferguson Tuesday night into early Wednesday, but they didn't turn violent, witnesses said.
At one point, police used tear gas to disperse a crowd, reports the St. Louis Post-Dispatch.
Police said death threats prompted them to withhold the name of the officer, who was placed on administrative leave after shooting Brown.
Investigators have released few details, saying only that a scuffle unfolded after the officer asked Brown and another teen to get out of the street. At some point, the officer's weapon fired inside a patrol car, police said.
"The local authorities have put themselves in a position - hiding names and not being transparent - where people will not trust anything but an objective investigation," Sharpton said during a news conference in St. Louis at which he was joined by Brown's parents.
He also echoed pleas for peaceful protests by the NAACP and Brown's father, Michael Brown Sr., who told the crowd, "I need all of us to come together and do this right. ... No violence."
President Obama also urged calm, saying people must comfort each other "in a way that heals, not in a way that wounds." Mr. Obama called Brown's death "heartbreaking."
Missouri Gov. Jay Nixon, whose appearance was unannounced, told a standing-room only crowd at a community forum Tuesday night that the shooting feels "like an old wound torn fresh" in a nation still struggling with race relations.
KMOV says Nixon didn't answer reporters' questions about whether he'd call out the National Guard if the civil unrest resumed in Ferguson.
The forum, held at a church, was organized as an alternative response to two nights of unrest in which crowds burned stores, vandalized vehicles, assaulted reporters and taunted officers. Ferguson's mayor and police chief also attended the meeting, and were welcomed with applause.
Earlier in the day, Police Chief Tom Jackson said he had decided against releasing the officer's name Tuesday after death threats were called in to police and City Hall and posted on social media. Jackson said it could be weeks before he releases the name.
(CBS News with KMOV)
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