CLEVELAND, Ohio (AFP) - Police arrested several people on Wednesday (July 20) outside the Republican National Convention in Cleveland as clashes erupted when protesters tried to burn American flags.

"Protesters refusing dispersal orders, pushing officers. A few arrests," the Cleveland Police Department posted on Twitter.

Tensions flared on the streets just one block from Quicken Loans Arena where Republicans anointed Donald Trump as their party's 2016 presidential nominee, as a man believed to have burned a flag was confronted by a counter-protester.

A group calling itself the Revolution Club sent out a press release earlier saying that Joey Johnson, a "notorious flag burner and revolutionary communist", would conduct the disobedience on the streets of Cleveland.

Security forces, including horse-mounted police, closed ranks around the protesters, and several detained people were seen kneeling with their hands behind their backs.

A woman also was seen being arrested as she sought to burn a second flag. Police intervened and tussled with protesters, and people chanted "Let her go!" as the woman was led away by police.

Demonstrations have taken place mostly peacefully in the city during the week of the convention, although scuffles have broken out during some protests.