Two journalists have been arrested while a TV crew was forced to flee from tear gas cannisters fired by police as they covered the aftermath of an officer shooting an unarmed black teenager last weekend in Ferguson, Missouri.
Wesley Lowery of the Washington Post and Ryan J Reilly of the Huffington Post were detained while covering protests about the fatal police shooting of 18-year-old Michael Brown.
Mr Reilly wrote on Facebook after his release that their apparent crime was "not packing up our gear quickly enough after a heavily armed Swat team shut down the McDonald's where we were working".
A Saint Louis County police officer in full riot gear, who refused to identify himself despite my repeated requests, purposefully banged my head against the window on the way out and sarcastically apologised. I'm fine. But if this is the way these officers treat a white reporter working on a laptop who moved a little too slowly for their liking, I can't imagine how horribly they treat others.
Separately Mr Lowery wrote an account of the incident for the Washington Post, saying police had told them they had been arrested for trespassing in a McDonald’s.
As they took me into custody, the officers slammed me into a soda machine, at one point setting off the Coke dispenser. They put plastic cuffs on me, then they led me out the door. I could see Ryan still talking to an officer. I said: “Ryan, tweet that they’re arresting me, tweet that they’re arresting me.” He didn’t have an opportunity, because he was arrested as well.
Inside the police van Mr Lowery was put in a large black man was calling for help, saying “I’m going to die! I can’t breathe! I’m going to die!” Mr Lowery tweeted later that he did not know what had happened to the man, adding: "Police officers (all white but one) belittling cries - desperate cries - for help of detained black man was absolutely horrifying to me."
As well as the arrest of two journalists in McDonald's, images show Al Jazeera staff fleeing after police shot a tear gas cannister next to them as they set up a live shot.
The team had been setting up their equipment but abandoned their cameras. Footage from KSDK, a local news channel, then shows police disassembling their cameras.
In a statement released today, Al Jazeera's Jocelyn Austin said rubber bullets had also been fired in the direction of the crew. Ms Austin said they were clearly identifiable as journalists, adding:
Police continued to shoot after crew members clearly and repeatedly shouted "press".
She added the assault was clearly designed to have a "chilling effect on our ability to cover this important story."
"Al Jazeera America is stunned by this egregious assault on freedom of the press that was clearly intended to have a chilling effect on our ability to cover this important story.
"We believe that this situation must be investigated along with those involving our colleagues at other media outlets."
In the aftermath of the arrests, the governor of Missouri Jay Nixon has tweeted urging police to respect the rights of the residents and press.