Michael Brown shooting - An armed man was fatally gunned down and remained in critical condition, after he exchanged fire with St. Louis County police officers late Sunday in Ferguson, Mo. marking the first year anniversary of the teenager's death.

Chief Jon Belmar of the St. Louise County Police said gunfire exploded when rival groups started shooting at each other on the west side of West Florissant Avenue, the center of the Ferguson protest. There had also been at least two other shootings not connected to protests in the area, The New York Times reported.

The shooting was condemned by Attorney General Loretta E. Lynch Monday, saying that "violence obscures any message of peaceful protest and places the community, as well as the officers who seek to protect it, in harm's way."

"The weekend's events were peaceful and promoted a message of reconciliation and healing," Ms. Lynch said in a statement. "But incidents of violence, such as we saw last night, are contrary to both that message, along with everything that all of us, including this group, have worked to achieve over the past year," Lynch said in a statement at a National Fraternal Order of Police conference in Pittsburgh.

According to Belmar, the wounded man was among the two groups firing at each other. His identity wasn't clear, but was later on identified as Tyrone Harris, 18, a close pal of Brown's, USA Today has learned.

Authorities said four plainclothes officer, who had closely watched the young lad run across a parking lot on the opposite side of the avenue, followed him in an unmarked sport utility vehicle, with its interior lights flashing. The man began shooting at the officers, who returned fire from inside the vehicle and then chased him on foot.

Dozens of gunshots were fired during the encounter between the four officers and the man before he was ultimately struck by a bullet, said Belmar.

A 9-millimeter Sig Sauer that was reported stolen last year, was recovered by cops from the shooting victim.

Meanwhile, Ferguson police also reported two male teens (17 and 19-year-old) were shot at around 2:15 a.m. at the Canfield Apartments Monday by a suspect wearing a red-hooded sweatshirt, USA Today has learned.

Each of the victims was shot once in the chest and transported to a local hospital, where they were treated for non-life-threatening injuries, cops said.

Three officers were injured, five people were arrested and several properties were announced damage by the St. Louis County police during the three-day protest which commemorates the Michael Brown shooting.

Lootings were also reported during the encounter with thieves even grabbing a cash register at a beauty supply shop. The suspects however, dropped the item in the street and took off when officers responded to the site.

Michael Brown was a high school graduate who died after he was fatally shot by Officer Darren Wilson during a confrontation, according to NBC News.

He reportedly stole items from a convenience store and nudged the owner who attempted to stop him on the morning of Aug. 9, 2014. Moments later, Wilson pulled up in a cruiser as Brown and a friend were walking on Canfield Drive, and the officer told them to move to the sidewalk.

A physical confrontation later on ensued, leading to the fatal gunning and eventually to his death.

The Michael Brown shooting ignited nightly protests for weeks. The tension grew when a St. Louis County grand jury declared Wilson had done nothing wrong. He resigned from duty days later.