Police were reportedly heard chanting “whose streets, our streets” after making arrests during the third consecutive night of protests in St Louis, Missouri. 

The protests were sparked by the acquittal of former St Louis police officer Jason Stockley in the fatal shooting of black man Anthony Lamar Smith.

David Carson, a reporter at the St Louis Post-Dispatch, said he had heard police chanting the slogan during Sunday night's clashes. 

Footage of the incident appeared to confirm his and other reporters' accounts, though the video remains inconclusive. 

Mr Carson said on Twitter: “I spoke with the commander at the scene, he said he did not hear the chant, but said chant was not acceptable, said he would deal with it.” St Louis police have been contacted for comment.

Witnesses say tonight's broken window vandalism downtown was caused by concrete chunks from broken potted plants like these. @ksdknews pic.twitter.com/K7d9uKo3k4

— Jacob Long (@JacobLong_KSDK) September 18, 2017

Person confronts line of bike police near Locust and Tucker #STLVerdict pic.twitter.com/UXD9zgVOVG

— Jesse Bogan (@JesseBogan) September 18, 2017

Police kettled tens of protesters in the early hours of Sunday morning before mass-arresting a number of those in the crowd. Among the arrests was local journalist Mike Faulk, who tweeted shortly before his arrest: We are closed in on all four sides... People freaking out".

We are closed in on all four sides now I have no idea where people are supposed to go. People freaking out #STLVerdict

— Mike Faulk (@Mike_Faulk) September 18, 2017

St Louis police department has also come under fire after footage showed an elderly woman being pushed to the ground in a clash with police.