Protestors immediately gathered at the scene of shooting. (Courtesy)

A teenage girl was reportedly shot by a police officer just moments before Derek Chauvin's guilty verdict was announced.

The 16-year-old has yet to be formally identified but local media are reporting the victim is named Ma'khia Bryant.

The shooting happened in Ohio, US, minutes before former cop Chauvin was found guilty on all counts of the murder of George Floyd.

Hazel Bryant – who told reporters she is Ma'khia's aunt – said her niece called police because she was being abused, The Daily Beast reported.

The girl "got into an altercation with someone else who lived at the same foster home", it has been reported.

Holding a knife – which she dropped – it is claimed, the teen was shot multiple times, her aunt told The Columbus Dispatch.

Officers are at the scene.

The teen's devastated mother Paula Bryant described her daughter as a "sweet child" who "didn’t deserve to die like a dog in the street".

She said: "She was a very loving, peaceful little girl. Ma'Kihia had a motherly nature about her. She promoted peace.

"That's something that I want to always be remembered."

Columbus Mayor Andrew Ginther said in a series of tweets: "This afternoon a young woman tragically lost her life. We do not know all of the details.

"There is body-worn camera footage of the incident. We are working to review it as soon as possible. BCI is on the scene conducting an independent investigation — as they do with all CPD-involved shootings.

Her aunt has spoken after the devastating incident.

"We will share information that we can as soon as it becomes available.

"I’m asking for residents to remain calm and allow BCI to gather the facts."

Chauvin was found guilty of the murder of the 46-year-old during his arrest last May.

He was found guilty of three counts of murder and manslaughter following the death of the black man last year.

Floyd's death in Minneapolis nearly a year ago sparked a wave of Black Lives Matter protests around the world.

Chauvin denied all charges against him, including second-degree unintentional murder, third-degree murder and second-degree manslaughter.

President Joe Biden said: "This systemic racism has left a stain on our nation's soul. Today's verdict is a step forward.

"We can and we must do more to ensure this type of tragedy doesn't happen again.

"Nobody should be above the law. We must restore trust."