Some police officers have joined protesters in the US following the death of African American George Floyd.

"The viral video of New York police kneeling with demonstrators Sunday dramatically documented the cracks that have formed in the thin blue line of America's law enforcement agencies as some officers denounced the death of George Floyd and sometimes joined the protests," NBC reported.

It quotes the police chief in Houston, Texas, where Floyd grew up Art Acevedo who said that Floyd's death should be "condemned by all in law enforcement and our extended community."

Last Saturday, he took part in a protest march in the city. Acevedo publicly expressed support for those who were outraged by the incident in Minneapolis on May 25.

When protesters arrived Saturday at the police station in Flint Township, Michigan, Chris Swanson, the sheriff of Genesee County, took off his helmet, laid down his baton and addressed the crowd.

"We want to be with y'all for real," Swanson told the crowd in video published by NBC affiliate WEYI of Flint, adding: "I want to make this a parade, not a protest. ... You just tell what you need to do."