Hundreds of Americans have held fresh Black Lives Matter demonstrations in protest at the deaths of two black people at the hands of police.
Alton Sterling, 37, was fatally shot by police in the southeastern city of Baton Rouge on July 5, and another African American, 32-year-old Philando Castile, was shot dead a day after by a police officer near St. Paul.
On Saturday, protesters again poured into the streets of US cities, including Miami in Florida, Baltimore in Maryland as well as the state of Michigan.
More than 20 people were arrested in a march that blocked Interstate 83 just north of downtown Baltimore.
The "Afromation" march began at Guilford Avenue and Chase Street, and moved through Artscape on Charles Street, then to St. Paul Street and past Penn Station to the I-83 on-ramp.
"Once on the interstate, they locked arms and blocked traffic along the northbound lanes for a short period of time before officers arrived and began making arrests," Baltimore police spokesman Lt. Jarron Jackson said.

According to protest organizer David Blair, demonstrators briefly blocked the interstate before officers told them to unblock the expressway to allow an ambulance to go through.
However, instead of an ambulance, two police vans drove through with more officers coming out.
The officers chased and corralled the protesters and began arresting the demonstrators, who were taken to Baltimore police's Northern District station.
In Miami, protesters gathered in Miami Gardens on Saturday afternoon, chanting slogans of “No justice, no peace” and “Black Lives Matter.”

“I’m just tired,” said 19-year-old Bianca Aldridge, who was attending the protest with her mother. “I don’t want to be scared of the police.”
Following the shootings of Sterling and Castile, thousands of people have been holding anti-police marches in different US cities.